| 1. Kulkarni AD, Jamieson DJ, Jones HW, Jr., et al. Fertility treatments and multiple births in the United States. N Engl J Med 2013;369:2218-25. |
Review/Other-Dx |
N/A |
To conduct a longitudinal analysis to determine the trends in and magnitude of the contribution of fertility treatments to multiple births. |
We estimated that by 2011, a total of 36% of twin births and 77% of triplet and higher-order births resulted from conception assisted by fertility treatments. The observed incidence of twin births increased by a factor of 1.9 from 1971 to 2009. The incidence of triplet and higher-order births increased by a factor of 6.7 from 1971 to 1998 and decreased by 29% from 1998 to 2011. This decrease coincided with a 70% reduction in the transfer of three or more embryos during IVF (P<0.001) and a 33% decrease in the proportion of triplet and higher-order births attributable to IVF (P<0.001). |
4 |
| 2. American College of Obstetricians and Gynecologists' Committee on Practice Bulletins-Obstetrics, Society for Maternal-Fetal Medicine. Multifetal Gestations: Twin, Triplet, and Higher-Order Multifetal Pregnancies: ACOG Practice Bulletin, Number 231. Obstet Gynecol. 137(6):e145-e162, 2021 Jun 01. |
Review/Other-Dx |
N/A |
To review the issues and complications associated with twin, triplet, and higher-order multifetal gestations and present an evidence-based approach to management. |
No results stated in abstract. |
4 |
| 3. Slaghekke F, Pasman S, Veujoz M, et al. Middle cerebral artery peak systolic velocity to predict fetal hemoglobin levels in twin anemia-polycythemia sequence. Ultrasound Obstet Gynecol. 46(4):432-6, 2015 Oct. |
Observational-Dx |
116 measurements (74 recorded in donors and 42 in recipients) from 43 twin pregnancies |
To evaluate the diagnostic accuracy of middle cerebral artery peak systolic velocity (MCA-PSV) Doppler measurements in prediction of hemoglobin levels in twin anemia-polycythemia sequence (TAPS). |
MCA-PSV multiples of the median (MoM) values correlated well with Hb levels (r = - 0.86; P < 0.001). The sensitivity of MCA-PSV >/= 1.5 MoM to predict severe anemia (Hb deficit > 5 SD below the mean) in TAPS donors was 94% (95% CI, 85-98%); specificity was 74% (95% CI, 62-83%); positive and negative predictive values were 76% (95% CI, 65-85%) and 94% (95% CI, 83-98%), respectively. The sensitivity of MCA-PSV </= 1.0 MoM to predict polycythemia (Hb level > 5 SD above the mean) in TAPS recipients was 97% (95% CI, 87-99%); specificity was 96% (95% CI, 89-99%); positive and negative predictive values were 93% (95% CI, 81-97%) and 99% (95% CI, 93-100%), respectively. |
2 |
| 4. Washburn EE, Sparks TN, Gosnell KA, Rand L, Gonzalez JM, Feldstein VA. Polyhydramnios Affecting a Recipient-like Twin: Risk of Progression to Twin-Twin Transfusion Syndrome and Outcomes. Am J Perinatol. 35(4):317-323, 2018 03. |
Observational-Dx |
64 twin pregnancies |
To assess the risk of progression to twin-twin transfusion syndrome (TTTS) with PART, progression to >/= stage II TTTS, and neonatal survival. |
Fifteen (23.4%) progressed to TTTS, including 10 (15.6%) who progressed to >/= stage II TTTS. Three pregnancies were terminated and one underwent selective reduction by radiofrequency ablation. Overall survival was 113 out of 128 (88.3%). Of those who remained stable, 91.8% (N = 45) had survival of both neonates. In multivariate analysis, the presence of arterioarterial (A-A) anastomosis by in utero Doppler ultrasound was associated with decreased risk of progression to TTTS (odds ratio: 0.12, p = 0.03, 95% confidence interval: 0.02-0.78). |
4 |
| 5. Jha P, Morgan TA, Kennedy A. US Evaluation of Twin Pregnancies: Importance of Chorionicity and Amnionicity. [Review]. Radiographics. 39(7):2146-2166, 2019 Nov-Dec. |
Review/Other-Dx |
N/A |
To describe the imaging findings that establish chorionicity and amnionicity. |
No results stated in abstract. |
4 |
| 6. Baxi LV, Walsh CA. Monoamniotic twins in contemporary practice: a single-center study of perinatal outcomes. J Matern Fetal Neonatal Med 2010;23:506-10. |
Review/Other-Dx |
25 MCMA pregnancies |
To assess perinatal mortality rates of monochorionic monoamniotic twins. |
Of the 25 MCMA pregnancies delivered, 98% (49/50) of twins were live-born. All women were delivered by cesarean section. There was one intrauterine fetal demise, which was secondary to anencephaly. There were three neonatal deaths, two in association with complex congenital heart disease. One twin died outside the neonatal period following cardiac surgery. In total, 28% (7/25) of pregnancies were complicated by major congenital anomalies. There was one case of mild transient twin-twin transfusion syndrome (TTTS). The overall perinatal mortality rate for non-anomalous twins was 2.4% (95% CI = 0.06%-13.59%). |
4 |
| 7. Lewi L, Jani J, Blickstein I, et al. The outcome of monochorionic diamniotic twin gestations in the era of invasive fetal therapy: a prospective cohort study. Am J Obstet Gynecol 2008;199:514 e1-8. |
Observational-Dx |
202 twin pairs |
To document pregnancy and neonatal outcome of monochorionic diamniotic twin pregnancies. |
Of the 202 included twin pairs, 172 (85%) resulted in 2 survivors, 15 (7.5%) in 1 survivor, and 15 (7.5%) in no survivors. The mortality was 45 of 404 (11%), and 36 of 45 (80%) were fetal losses of 24 weeks or less, 5 of 45 (11%) between 24 weeks and birth, and 4 of 45 (9%) were neonatal deaths. Twin-to-twin transfusion syndrome (TTTS) occurred in 18 of 202 (9%). The mortality of TTTS was 20 of 36 (55%), which accounted for 20 of 45 (44%) of all losses. Severe discordant growth without TTTS occurred in 29 of 202 (14%). Its mortality was 5 of 58 (9%), which accounted for 5 of 45 (11%) of all losses. Major discordant congenital anomalies occurred in 12 of 202 (6%). Of the 178 pairs that continued after 24 weeks, 10 (6%) had severe hemoglobin differences at birth. After 32 weeks, the prospective risk of intrauterine demise was 2 in 161 pregnancies (1.2%; 95% confidence interval, 0.3-4.6). |
3 |
| 8. Fichera A, Prefumo F, Stagnati V, Marella D, Valcamonico A, Frusca T. Outcome of monochorionic diamniotic twin pregnancies followed at a single center. Prenat Diagn 2015;35:1057-64. |
Observational-Dx |
300 monochorionic diamniotic twin pregnancies |
To review our experience and to report the pregnancy and neonatal outcome of a cohort of MCDA twin pregnancies followed from the first trimester onwards at a single center over an 11-year period |
There were two surviving infants in 259/300 (86.4%) pregnancies, one survivor in 22/300 (7.3%) and no survivors in 19/300 (6.3%) with an overall mortality of 60/600 (10%). Twin-twin transfusion syndrome was diagnosed in 33 cases (11%), isolated intertwin weight discordance >/= 25% in 35 (11.6%) and major congenital structural anomalies in ten (3.3%). After 32 weeks, the prospective risk of spontaneous fetal intrauterine death was one in 248 (0.4%) per pregnancy. |
4 |
| 9. Hoskins IA, Combs CA. Society for Maternal-Fetal Medicine Special Statement: Updated checklists for management of monochorionic twin pregnancy. Am J Obstet Gynecol. 223(5):B16-B20, 2020 11. |
Review/Other-Dx |
N/A |
To present updated checklists for management of monochorionic twin pregnancy |
No results stated in abstract. |
4 |
| 10. Dias T, Mahsud-Dornan S, Bhide A, Papageorghiou AT, Thilaganathan B. Cord entanglement and perinatal outcome in monoamniotic twin pregnancies. Ultrasound Obstet Gynecol 2010;35:201-4. |
Review/Other-Dx |
32 monoamniotic pregnancies |
To assess the prevalence of cord entanglement and perinatal outcome in a large series of monoamniotic twin pregnancies and to review the recent literature on similar published large series. |
A total of 32 monoamniotic pregnancies were diagnosed during the study period, including three conjoined twins, seven pregnancies with twin reversed arterial perfusion (TRAP) syndrome, three surgical pregnancy interruptions for discordant fetal abnormality and one miscarriage before 16 weeks' gestation. The remaining 18 monoamniotic pregnancies were included in the study analysis. All monoamniotic pregnancies were complicated with antenatal cord entanglement diagnosed by B-mode and color Doppler ultrasound. There were 34 live births and a double intrauterine death diagnosed at 19 + 2 weeks' gestation. There were two late neonatal deaths, one from congenital complete heart block and the other after surgery for transposition of the great arteries. The overall perinatal loss rate was 11.1% after 16 weeks and 5.9% after 20 weeks' gestation. The cumulative rates of cord entanglement and perinatal mortality in the reviewed literature were 74% and 21%, respectively. |
4 |
| 11. Cordero L, Franco A, Joy SD. Monochorionic monoamniotic twins: neonatal outcome. Journal of perinatology : official journal of the California Perinatal Association 2006;26:170-5. |
Review/Other-Dx |
36 sets of twins |
To report our experience with 36 sets of MoMo twins (1990 to 2005) and to provide updated information for counseling. |
Cord entanglement was observed in 15 pregnancies, but only one twin with entanglement and a true knot, experienced related morbidity. Four of 71 live births were IUGR. Malformations were diagnosed prenatally (one hypoplastic left heart and one body stalk) and postnatally (one vertebral anomalies-anal atresia-tracheoesophageal fistula-renal defect (VATER) and two lung hypoplasias). Twin-to-twin transfusion syndrome affected three sets of twins. Five twin sets delivered before 31, 19 sets at 31 to 32 and 12 sets at 33 to 34 weeks. Six of 71 (8%) twins died (four malformations, one TTS and one 26 weeks premature). Head ultrasounds in 59 of 65 survivors showed two (3%) periventricular leukomalacia, five (9%) Grade I-II intraventricular hemorrhage and 52 (88%) normal. |
4 |
| 12. McDonald R, Hodges R, Knight M, et al. Optimal Interval between Ultrasound Scans for the Detection of Complications in Monochorionic Twins. Fetal Diagn Ther. 41(3):197-201, 2017. |
Observational-Dx |
162 patients |
To provide insight into the optimal interval of ultrasound surveillance. |
A total of 162 women with MCDA pregnancies attended our care. Six women were excluded due to late referral. Of the remaining 156, 55% were uncomplicated. TTTS, TAPS, IUGR and fetal demise in utero occurred in 9%, 1%, 31% and 2%, respectively. Median interval between the last ultrasound and TTTS diagnosis was 3.1 weeks (IQR 0.8-5.8). There was a trend towards a longer interval for cases with advanced TTTS compared to early TTTS. Interval between ultrasound scans was longer in cases with unexplained fetal demise in utero and advanced TTTS than early TTTS [3.4 weeks (IQR 2.0-6.9) vs. 0.9 weeks (IQR 0.4-3.7); p < 0.05]. |
3 |
| 13. Kawaguchi H, Ishii K, Muto H, Yamamoto R, Hayashi S, Mitsuda N. The incidence of unexpected critical complications in monochorionic diamniotic twin pregnancies according to the interval period between ultrasonographic evaluations. J Obstet Gynaecol Res. 45(2):318-324, 2019 Feb. |
Observational-Dx |
385 patients |
To evaluate the incidence of unexpected critical complications (UCC) in monochorionic diamniotic (MCDA) twin pregnancies according to ultrasonographic scan interval. |
Of all 385 cases, the total incidence of UCC was 20 (5.2%), including 14 cases of twin-twin transfusion syndrome and 6 cases of intrauterine fetal death. The incidence of UCC was 3.9% in Group A and 9.0% in Group B (P = 0.046). In contrast, the incidence of predictable critical complications was 6.7% in Group A and 9.0% in Group B (P = 0.440). |
4 |
| 14. Syngelaki A, Cimpoca B, Litwinska E, Akolekar R, Nicolaides KH. Diagnosis of fetal defects in twin pregnancies at routine 11-13-week ultrasound examination. Ultrasound Obstet Gynecol. 55(4):474-481, 2020 04. |
Observational-Dx |
6366 twin pregnancies with two live fetuses |
To examine the performance of the routine 11-13-week scan in detecting fetal defects in twin pregnancies and to examine if, in pregnancies with a fetal defect, compared to those with normal fetuses, there is increased incidence of nuchal translucency thickness (NT) >/= 95(th) and >/= 99(th) percentiles or intertwin discordance in crown-rump length (CRL) >/= 10% and >/= 15%. |
The main findings were: first, the overall incidence of fetal defects was higher in MC than in DC twins (2.8% vs 1.3%); second, the proportion of defects diagnosed in the first trimester was higher in MC than in DC twins (52.6% vs 27.1%); third, the pattern of defects in relation to detectability at the 11-13-week scan (always detectable, sometimes detectable and never detectable) was similar to that reported previously in singleton pregnancies; fourth, always-detectable defects included acrania, alobar holoprosencephaly, encephalocele, pentalogy of Cantrell, exomphalos, body-stalk anomaly, twin reversed arterial perfusion sequence and conjoined twins; fifth, the incidence of fetal NT >/= 95(th) percentile was higher in those with than in those without a defect (16.5% vs 4.5% in DC twins and 19.2% vs 5.9% in MC twins) and this was also true for NT >/= 99(th) percentile (8.3% vs 1.0% in DC twins and 15.4% vs 2.0% in MC twins); and sixth, the incidence of CRL discordance >/= 10% was higher in those with than in those without a defect (20.2% vs 7.9% in DC twins and 33.8% vs 9.3% in MC twins) and this was also true for CRL discordance >/= 15% (10.1% vs 1.9% in DC twins and 28.2% vs 2.8% in MC twins). |
3 |
| 15. AIUM Practice Parameter for the Performance of Detailed Diagnostic Obstetric Ultrasound Examinations Between 12 Weeks 0 Days and 13 Weeks 6 Days. J Ultrasound Med 2021;40:E1-E16. |
Review/Other-Dx |
N/A |
To present a practice parameter document for standard diagnostic obstetric ultrasound examination. |
No results stated in abstract. |
4 |
| 16. Bsat F, Fisher BM, Malisch T, Jain V. Fetal Echocardiogram and Detailed First Trimester Obstetric Ultrasound: ICD-10 Indications. Am J Perinatol 2023;40:25-27. |
Review/Other-Dx |
N/A |
present the corresponding International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes for indications for fetal echocardiogram and for the detailed first trimester obstetric ultrasound. |
No results stated in abstract. |
4 |
| 17. van Klink JM, van Steenis A, Steggerda SJ, et al. Single fetal demise in monochorionic pregnancies: incidence and patterns of cerebral injury. Ultrasound Obstet Gynecol. 45(3):294-300, 2015 Mar. |
Observational-Dx |
49 MC pregnancies with single fetal demise |
To evaluate the incidence, type and severity of cerebral injury in the surviving monochorionic (MC) cotwin after single fetal demise in twin pregnancies. |
Median gestational age at occurrence of single fetal demise was 25 weeks and median interval between single fetal demise and live birth was 61 days, with a median gestational age at birth of 36 weeks. Severe cerebral injury was diagnosed in 13 (26%) of the 50 cotwins and was detected antenatally in 4/50 (8%) and postnatally in 9/50 (18%) cases. Cerebral injury was mostly due to hypoxic-ischemic injury resulting in cystic periventricular leukomalacia, middle cerebral artery infarction or injury to basal ganglia, thalamus and/or cortex. Risk factors associated with severe cerebral injury were advanced gestational age at the occurrence of single fetal demise (odds ratio (OR), 1.14 (95% CI, 1.01-1.29) for each week of gestation; P = 0.03), twin-twin transfusion syndrome developing prior to single fetal demise (OR, 5.0 (95% CI, 1.30-19.13); P = 0.02) and a lower gestational age at birth (OR, 0.83 (95% CI, 0.69-0.99) for each week of gestation; P = 0.04). |
3 |
| 18. Robinson A, Teoh M, Edwards A, Fahey M, Goergen S. Fetal brain injury in complicated monochorionic pregnancies: diagnostic yield of prenatal MRI following surveillance ultrasound and influence on prognostic counselling. Prenat Diagn. 37(6):611-627, 2017 Jun. |
Observational-Dx |
33 patients with 48 lives fetuses |
To determine the additional diagnostic information provided by prenatal (fetal) magnetic resonance imaging (pMRI) following tertiary ultrasound (US) for fetal cranial abnormalities in complicated monochorionic gestations. |
Three of ten survivors of spontaneous CD, one of eight survivors of CD after twin-twin transfusion syndrome and 1/30 co-survivors had diagnostic information added by pMRI that altered counselling; US was normal in two and in the other three underrepresented parenchymal injury (5/33 = 15%; 95% confidence interval +/-0.27-0.03). Additional findings included occipital lobe infarction, hemispheric injury, dural sinus thrombosis, ischaemia-producing polymicrogyria and intraventricular haemorrhage. Another 8/33 women had additional information provided by pMRI that did not alter counselling. |
3 |
| 19. Aertsen M, Van Tieghem De Ten Berghe C, Deneckere S, Couck I, De Catte L, Lewi L. The prevalence of brain lesions after in utero surgery for twin-to-twin transfusion syndrome on third-trimester MRI: a retrospective cohort study. Eur Radiol. 31(6):4097-4103, 2021 Jun. |
Observational-Dx |
141 patients treated with laser coagulation and 17 managed by cord occlusion |
To determine the prevalence of antenatal brain lesions detected on third-trimester MRI and the proportion of lesions detected exclusively on MRI. |
Of those, 69/112 (62%) and 11/15 (73%) underwent an MRI between 28 and 32 weeks. After laser coagulation, MRI detected an antenatal brain lesion in 6 of 69 pregnancies (9%) or in 6 of 125 fetuses (5%). In 4 cases (67%), the lesion was detected only on MRI. In the 11 patients treated with cord occlusion, no brain lesions were diagnosed. |
3 |
| 20. American College of Radiology. ACR-SPR Practice Parameter for Imaging Pregnant or Potentially Pregnant Patients with Ionizing Radiation. Available at: http://www.acr.org/~/media/ACR/Documents/PGTS/guidelines/Pregnant_Patients.pdf. |
Review/Other-Dx |
N/A |
To assist practitioners in providing appropriate radiologic care for pregnant or potentially pregnant adolescents and women by describing specific training, skills and techniques. |
No abstract available. |
4 |
| 21. American College of Radiology. ACR Committee on Drugs and Contrast Media. Manual on Contrast Media. Available at: https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf. |
Review/Other-Dx |
N/A |
Guidance document to assist radiologists in recognizing and managing the small but real risks inherent in the use of contrast media. |
No abstract available. |
4 |
| 22. American College of Radiology. Gadolinium Pregnancy Screening Statement. Available at: https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Gadolinium-Pregnancy-Screening-Statement---FINAL.pdf. |
Review/Other-Dx |
N/A |
To present the statement on gadolinium pregnancy screening. |
No results stated in abstract. |
4 |
| 23. Sassoon DA, Castro LC, Davis JL, Hobel CJ. Perinatal outcome in triplet versus twin gestations. Obstet Gynecol 1990;75:817-20. |
Observational-Dx |
15 triplet and twin pregnancies |
To determine whether triplet pregnancies are associated with a significantly worse perinatal outcome than twin pregnancies |
Maternal and neonatal outcome was evaluated in 15 triplet and twin pregnancies that were matched for maternal age, race, type of medical insurance, delivery mode, parity, and history of previous preterm delivery. Preterm labor occurred significantly more often in triplet than in twin gestations (80 versus 40%), as did preterm delivery (87 versus 26.7%). Triplets had a significantly lower mean birth weight (1720 versus 2475 g) and gestational age at delivery (33 versus 36.6 weeks). In addition, 53.3% of triplet pregnancies but only 6.7% of twin pregnancies had one or more neonates with intrauterine growth retardation. Discordancy also occurred more frequently in triplets than in twins (66.7 versus 13.3%). The mean averaged neonatal hospital stay was significantly higher in triplets (29 versus 8.5 days), and triplets had a fivefold increased risk of requiring neonatal intensive care as compared with twins. However, there were no significant differences between the groups in maternal morbidity or major neonatal complications such as respiratory distress syndrome or intraventricular hemorrhage. |
3 |
| 24. Maruotti GM, Saccone G, Morlando M, Martinelli P. First-trimester ultrasound determination of chorionicity in twin gestations using the lambda sign: a systematic review and meta-analysis. [Review]. Eur J Obstet Gynecol Reprod Biol. 202:66-70, 2016 Jul. |
Meta-analysis |
9 studies |
To evaluate the accuracy of first-trimester sonographic determination of chorionicity in twin gestations using the lambda sign. |
Nine studies, including 2292 twins, were analysed. In all of these studies, identification of the lambda sign was used to diagnose chorionicity on real-time B-mode imaging. Twins were classified as monochorionic if there was a single placental mass in the absence of the lambda sign, and dichorionic if there was a single placental mass but the lambda sign was present or the placentas were not adjacent to each other. In all nine studies, placental histology or discordant fetal sex were used to confirm chorionicity. Pooled results from the meta-analysis showed that sensitivity of the presence of the lambda sign in the prediction of dichorionicity was 99% (95% CI 98-100%), and specificity was 95% (95% CI 92-97%). Pooled sensitivity of the absence of the lambda sign in the prediction of monochorionicity was 96% (95% CI 92-98%) and pooled specificity was 99% (95% CI 98-99%). The AUC for diagnostic accuracy was 0.99, and suggested very high diagnostic accuracy. |
Good |
| 25. Gordon MC, McKenna DS, Stewart TL, et al. Transvaginal cervical length scans to prevent prematurity in twins: a randomized controlled trial. Am J Obstet Gynecol. 214(2):277.e1-277.e7, 2016 Feb. |
Observational-Dx |
125 dichorionic or monochorionic/diamniotic twin pregnancies |
To determine whether use of TVCL prolongs gestation in twin pregnancies. |
The mean gestational age at delivery was 35.7 weeks (95% confidence interval [CI], 35.2-36.2) among those managed with TVCL and 35.5 weeks (95% CI, 34.7-36.4) among the control patients. The Kaplan-Meier estimates of deliveries <38 weeks were not significantly different between groups. This was true whether we compared curves with a log-rank test (P = .67), Breslow test (P = .67), or Tarone-Ware test (P = .64). The percentage of deliveries <35 0/7 weeks did not differ: 27.4% for subjects managed with routine TVCL and 28.6% for control subjects (relative risk, 0.96; 95% CI, 0.60-1.54). Our study had an 80% power to detect a 12-day difference in the gestational age at delivery with 95% confidence. |
3 |
| 26. Hester AE, Ankumah NE, Chauhan SP, Blackwell SC, Sibai BM. Twin transvaginal cervical length at 16-20 weeks and prediction of preterm birth. J Matern Fetal Neonatal Med. 32(4):550-554, 2019 Feb. |
Observational-Dx |
655 patients |
To determine if transvaginal cervical length at 16-20 weeks is predictive of preterm birth <34 weeks in a large cohort of twin pregnancies. |
Of 655 pregnancies, 27% (N = 178) women met our inclusion criteria. The rate of spontaneous preterm birth before 34 weeks was 16% (N = 29). A receiver operator characteristic curve was generated for all preterm birth <34 weeks (spontaneous and indicated) which demonstrated an area under the curve of 0.51, 95% CI (0.41-0.61). When indicated preterm birth (n = 15) were excluded, the area under the curve was 0.59 (95% CI 0.47-0.70), indicating that transvaginal cervical length values were not a clinically useful test for the prediction of spontaneous preterm birth. A transvaginal cervical length of 30 mm from this model would produce a sensitivity of detecting spontaneous preterm birth of 95% and a specificity of 14%. |
4 |
| 27. Park SY, Chung JH, Han YJ, Lee SW, Kim MY. Prediction of Amnionicity Using the Number of Yolk Sacs in Monochorionic Multifetal Pregnancy. J Korean Med Sci. 32(12):2016-2020, 2017 Dec. |
Observational-Dx |
97 patients |
To evaluate the accuracy of predicting amnionicity using the number of yolk sacs by diagnostic ultrasound examination in monochorionic (MC) multifetal pregnancies between 7 + 0 and 9 + 6 gestational weeks. |
Overall, there was a 9.3% (9 cases) discrepancy in number of yolk sacs and amnionicity (4.3% for monochorionic diamniotic, 36.4% for monochorionic monoamniotic, and 33% for monochorionic triamniotic). Among the 9 cases with discrepancies, 4 cases with 2 yolk sacs were confirmed as monoamniotic pregnancies and 4 MC twin pregnancies showing a single yolk sac were diagnosed as diamniotic twin pregnancies. One case with 2 yolk sacs was identified as a triamniotic triplet pregnancy. In 9.3% of MC gestations, the number of yolk sacs was not correlated with the number of amnions in our study. |
4 |
| 28. Dias T, Arcangeli T, Bhide A, Napolitano R, Mahsud-Dornan S, Thilaganathan B. First-trimester ultrasound determination of chorionicity in twin pregnancy. Ultrasound Obstet Gynecol 2011;38:530-2. |
Observational-Dx |
648 pregnancies |
To determine the accuracy of ultrasound at 11-14 weeks' gestation in the diagnosis of chorionicity in twin pregnancy. |
A total of 648 pregnancies were assigned chorionicity by first-trimester ultrasound during the study period. Chorionicity was ascertained in 613 cases, either by histology (n = 340) or discordant sex (n = 273). Chorionicity was correctly assigned by ultrasound at 11-14 weeks in 612 of 613 pregnancies (accuracy 99.8%). Sensitivity and specificity for determining monochorionicity were 100% and 99.8%, respectively. |
3 |
| 29. Johansen ML, Oldenburg A, Rosthoj S, Cohn Maxild J, Rode L, Tabor A. Crown-rump length discordance in the first trimester: a predictor of adverse outcome in twin pregnancies?. Ultrasound Obstet Gynecol. 43(3):277-83, 2014 Mar. |
Observational-Dx |
1993 twin pregnancies |
To evaluate the usefulness of first-trimester crown-rump length (CRL) discordance in predicting adverse outcome in twin pregnancies. |
Among 1993 twin pregnancies, 1733 were dichorionic (156 (9%) discordant; 1577 (91%) concordant) and 260 were monochorionic (32 (12%) discordant; 228 (88%) concordant). In dichorionic twin pregnancies we found an association between CRL discordance >/= 10% and preterm delivery before 34 weeks' gestation (P=0.007), birth weight discordance (P=0.001) and mean birth weight (P=0.033). In monochorionic twin pregnancies we found an association between CRL discordance >/= 10% and birth weight discordance (P=0.02) and mean birth weight (P=0.03). To evaluate CRL discordance as a predictor of fetal loss and preterm delivery before 34 weeks' gestation, receiver-operating characteristics curves were created for each outcome. For CRL discordance >/= 10% as a predictor of fetal loss and preterm delivery in dichorionic twin pregnancies, sensitivity was 0.17 (95% CI, 0.06-0.28) and 0.14 (95% CI, 0.10-0.18), respectively, and in monochorionic twin pregnancies it was 0.10 (95% CI, 0.03-0.22) and 0.16 (95% CI, 0.06-0.26), respectively. |
4 |
| 30. Ben-Ami I, Daniel-Spiegel E, Battino S, et al. The association of crown-rump length discrepancy with birthweight discordance in spontaneous versus IVF monochorionic twins: a multicenter study. Prenat Diagn. 35(9):864-9, 2015 Sep. |
Observational-Dx |
171 pregnancies |
To compare the associations of crown-rump length (CRL) discrepancy with birthweight discordance in spontaneous versus in vitro fertilization (IVF) monochorionic (MC) twin pregnancies. |
In the entire cohort, we found a significant correlation between birthweight discordance and CRL discrepancy (r = 0.173, P < 0.05). While a significant correlation was found between CRL discrepancy and birthweight discordance in spontaneous-conceived pregnancies (n = 142, r = 0.24, P = 0.005), such correlation was not present in IVF pregnancies (n = 29, r = -0.7, P = 0.724). A logistic regression analysis found significant odds of larger-weight discordance for each increase of 1% in CRL discrepancy among spontaneously conceived pregnancies (odds ratio = 1.1, confidence interval = 1.03-1.2, P = 0.005). A receiver operating characteristic (ROC) for large-weight discordance in the spontaneously conceived pregnancies demonstrated an area under the ROC curve of 0.613 (P = 0.039). |
3 |
| 31. Grande M, Gonce A, Stergiotou I, Bennasar M, Borrell A. Intertwin crown-rump length discordance in the prediction of fetal anomalies, fetal loss and adverse perinatal outcome. J Matern Fetal Neonatal Med. 29(17):2883-8, 2016 Sep. |
Observational-Dx |
471 twin pregnancies |
To assess the risks of fetal anomalies, fetal loss and adverse perinatal outcome in a cohort of first-trimester intertwin crown-rump length (CRL) discordant twins, stratified by chorionicity and the degree of CRL discordance. |
Discordant twin pregnancies were at significant higher risk of chromosomal (OR = 11.42; 95% CI: 2.78-46.94) and structural anomalies (OR = 5.91; 95% CI: 2.25-15.54), spontaneous fetal loss (OR = 4.23; 95% CI: 1.79-10.01), birthweight discordance (OR = 2.8; 95% CI: 1.48-5.65) and small-for-gestational age (OR = 3.48; 95% CI: 1.78-6.79). Similar differences (except for birthweight discordance) were observed among dichorionic twins. Among monochorionic, increased frequencies were only seen for structural anomalies, birthweight discordance and small newborns. Severe CRL discordance presented with higher rates of structural anomalies, stillbirth, birthweight discordance and small newborns. |
3 |
| 32. Eschbach SJ, Boons L, Van Zwet E, et al. Right ventricular outflow tract obstruction in complicated monochorionic twin pregnancy. Ultrasound Obstet Gynecol 2017;49:737-43. |
Observational-Dx |
485 pregnancies |
To evaluate pregnancy characteristics of neonates with right Ventricular Outflow Tract Obstruction (RVOTO) in complicated monochorionic twin pregnancies. |
A total of 485 twin pregnancies received laser therapy for Twin-to-Twin-Transfusion Syndrome (TTTS). RVOTO was diagnosed in 3.0% (11/385) of the live born TTTS-recipients. Two of them showed a mild Ebstein anomaly additionally. Before laser therapy, pericardial effusion was seen in 45% (5/11) of RVOTO cases (p < 0.01), abnormal A-wave in ductus venosus (DV) was seen in 73% (8/11) (p = 0.03) and gestational age at time of laser therapy was 17w3d compared to 20w3d in controls (p = 0.03). A prediction model was constructed. One donor had RVOTO after development of transient hydrops after laser therapy. Three larger twins in pregnancies complicated by sIUGR developed RVOTO, in all three cases onset of RVOTO was visible in early second trimester. |
3 |
| 33. D'Antonio F, Familiari A, Thilaganathan B, et al. Sensitivity of first-trimester ultrasound in the detection of congenital anomalies in twin pregnancies: population study and systematic review. Acta Obstet Gynecol Scand. 95(12):1359-1367, 2016 Dec. |
Observational-Dx |
1064 twin pregnancies |
To ascertain the diagnostic performance of first-trimester ultrasound in detecting congenital anomalies in twins. |
Forty-two pregnancies had one or more fetuses with structural abnormalities. Detection of structural abnormalities using ultrasound was possible in the first trimester in 27.3% (95% confidence interval 15.0-42.8) of twin pregnancies. Monochorionicity (odds ratio 2.3, 95% confidence interval 1.1-4.7) and discordance in crown-rump length and nuchal translucency were associated with an increased risk of fetal anomalies. However, their predictive accuracy was only moderate (areas under the curve 0.67, 95% confidence interval 0.6-0.8 and 0.68, 95% confidence interval 0.6-0.8, for crown-rump length and nuchal translucency discrepancy, respectively). |
3 |
| 34. D'Antonio F, Khalil A, Pagani G, Papageorghiou AT, Bhide A, Thilaganathan B. Crown-rump length discordance and adverse perinatal outcome in twin pregnancies: systematic review and meta-analysis. Ultrasound Obstet Gynecol 2014;44:138-46. |
Review/Other-Dx |
17 studies |
To explore the relationship between crown-rump length (CRL) discordance detected at 11-14 weeks of gestation and adverse outcome in twin pregnancy and to assess its predictive accuracy. |
A total of 2008 articles were identified and 17 studies were included in the systematic review. Twin pregnancies with CRL discordance >/= 10% were at significantly higher risk of perinatal loss (RR, 2.80; 95% CI, 1.25-6.27; P = 0.012), fetal loss at >/= 24 weeks (RR, 4.07; 95% CI, 1.47-11.23; P = 0.006), BW discordance (RR, 2.24; 95% CI, 1.89-2.64; P < 0.001) and PTD at < 34 weeks (RR, 1.49; 95% CI, 1.23-1.80; P < 0.001) but not of fetal loss at < 24 weeks (P = 0.130). A meta-analysis of fetal anomalies was not possible because fewer than two studies explored this outcome. However, when used alone to screen for adverse pregnancy outcome, the predictive accuracy of CRL discordance was low for each of the outcomes explored. |
4 |
| 35. Litwinska E, Syngelaki A, Cimpoca B, Sapantzoglou I, Nicolaides KH. Intertwin discordance in fetal size at 11-13 weeks' gestation and pregnancy outcome. Ultrasound Obstet Gynecol. 55(2):189-197, 2020 02. |
Observational-Dx |
6225 twin pregnancies |
To investigate the value of intertwin discordance in fetal crown-rump length (CRL) at the 11-13-week scan in the prediction of adverse outcome in dichorionic (DC), monochorionic diamniotic (MCDA) and monochorionic monoamniotic (MCMA) twin pregnancies. |
First, the study population of 6225 twin pregnancies included 4896 (78.7%) DC, 1274 (20.4%) MCDA and 55 (0.9%) MCMA twin pregnancies. Second, median CRL discordance in DC twin pregnancies (3.2%; interquartile range (IQR), 1.4-5.8%) was lower than in MCDA twins (3.6%; IQR, 1.6-6.2%; P = 0.0008), but was not significantly different from that in MCMA twins (2.9%; IQR, 1.2-5.1%; P = 0.269). Third, compared to CRL discordance in DC twin pregnancies with two non-SGA live births at >/= 37 weeks' gestation, there was significantly larger CRL discordance in both DC and MCDA twin pregnancies complicated by fetal death at < 20 and < 24 weeks' gestation, perinatal death at >/= 24 weeks, preterm birth at < 32 and < 37 weeks, birth of at least one SGA neonate and birth-weight discordance >/= 20% and >/= 25%, and in MCDA twin pregnancies undergoing endoscopic laser surgery. Fourth, the predictive performance of CRL discordance for each adverse pregnancy outcome was poor, with areas under the receiver-operating-characteristics curves ranging from 0.533 to 0.624. However, in both DC and MCDA twin pregnancies with large CRL discordance, there was a high risk of fetal loss. Fifth, in DC twin pregnancies, the overall rate of fetal loss at < 20 weeks' gestation was 1.3% but, in the small subgroup with CRL discordance of >/= 15%, which constituted 1.9% of the total, the rate increased to 5.3%. Sixth, in MCDA twin pregnancies, the rate of fetal loss or endoscopic laser surgery at < 20 weeks was about 11%, but, in the small subgroups with CRL discordance of >/= 10%, >/= 15% and >/= 20%, which constituted 9%, < 3% and < 1% of the total, the risk was increased to about 32%, 49% and 70%, respectively. Seventh, in MCMA twin pregnancies, there were no significant differences in CRL discordance for any of the adverse outcome measures, but this may be the consequence of the small number of cases in the study population. |
3 |
| 36. Kagan KO, Gazzoni A, Sepulveda-Gonzalez G, Sotiriadis A, Nicolaides KH. Discordance in nuchal translucency thickness in the prediction of severe twin-to-twin transfusion syndrome. Ultrasound Obstet Gynecol 2007;29:527-32. |
Observational-Dx |
512 monochorionic twin pregnancies |
To examine in monochorionic pregnancies the possible value of intertwin discordance in nuchal translucency (NT) thickness in the prediction of early fetal death or severe twin-twin transfusion syndrome (TTTS). |
In 412 (80.5%) pregnancies there was a normal outcome, in 58 (11.3%) there was severe TTTS requiring endoscopic laser surgery at 18-24 weeks, in 19 (3.7%) there was death of one or both fetuses at 13-18 weeks and in 23 (4.5%) there was fetal death at 21-38 weeks. In the four outcome groups the median discordance in NT was 11%, 22%, 35% and 7%, respectively. Significant prediction of early fetal death and severe TTTS was provided by the discordance in fetal NT, which was not significantly improved by including the discordance in crown-rump length. If the discordance in NT was 20% or more, the false positive rate was 20%, the detection rate of early fetal death was 63% and the detection rate of severe TTTS was 52%. |
3 |
| 37. Cimpoca B, Syngelaki A, Litwinska E, Muzaferovic A, Nicolaides KH. Increased nuchal translucency at 11-13 weeks' gestation and outcome in twin pregnancy. Ultrasound Obstet Gynecol. 55(3):318-325, 2020 03. |
Observational-Dx |
6225 twin pregnancies |
To investigate the value of increased fetal nuchal translucency thickness (NT) at the 11-13-week scan in the prediction of adverse outcome in dichorionic (DC), monochorionic diamniotic (MCDA) and monochorionic monoamniotic (MCMA) twin pregnancies. |
The incidence of NT >/= 95(th) percentile in one or both fetuses in DC twin pregnancies was 8.3%; in MCDA twins the incidence was significantly higher (10.4%; P = 0.016), but in MCMA twins it was not significantly different (9.1%; P = 0.804) from that in DC twins. In DC twin pregnancies, the incidence of high NT was not significantly different between those with two survivors and those with adverse outcome. In MCMA twin pregnancies, the number of cases was too small for meaningful assessment of the relationship between high NT and adverse outcome. In MCDA twin pregnancies with at least one fetal death or need for endoscopic laser surgery at < 20 weeks' gestation, the incidence of NT >/= 95(th) percentile was significantly higher than in those with two survivors (23.5% vs 9.8%; P < 0.0001). Kaplan-Meier analysis in MCDA twin pregnancies showed that, in those with NT >/= 95(th) percentile, there was significantly lower survival at < 20 weeks' gestation than in those with NT < 95(th) percentile (P = 0.001); this was not the case for survival at >/= 20 weeks (P = 0.960). The performance of screening by fetal NT >/= 95(th) percentile for prediction of either fetal loss or need for endoscopic laser surgery at < 20 weeks' gestation was poor, with a detection rate of 23.5% at a false-positive rate of 8.9%, and the relative risk, in comparison to fetal NT < 95(th) percentile, was 2.640 (95% CI, 1.854-3.758; P < 0.0001). In MCDA twin pregnancies, the overall rate of fetal loss or need for laser surgery at < 20 weeks' gestation was 10.7% but, in the subgroups with NT >/= 95(th) and NT >/= 99(th) percentiles, which constituted 10.4% and 3.3% of the total, the rates increased to 24.1% and 40.5%, respectively. |
3 |
| 38. Edlow AG, Reiss R, Benson CB, Gerrol P, Wilkins-Haug L. Monochorionic diamniotic twin gestations discordant for markedly enlarged nuchal translucency. Prenatal Diagnosis. 31(3):299-306, 2011 Mar. |
Review/Other-Dx |
162 twin pairs |
To assess karyotypes and outcomes of monochorionic diamniotic (MCDA) twin pregnancies discordant for markedly enlarged nuchal translucency (NT) in the first trimester. |
Of 162 MCDA twin pairs, 11 were discordant for NT >/= 3.5. Chromosomal abnormalities were present in three cases: one twin pair was concordant for trisomy 18; one pair discordant for mosaic trisomy 2; and one pair discordant for confined placental mosaicism (CPM) (high frequency tetraploidy). Adverse outcomes for twins with euploid or unknown karyotypes included twin reverse arterial perfusion (TRAP) sequence, growth discordance, and esophageal atresia with tracheoesophageal fistula. |
4 |
| 39. Zipori Y, Reidy K, Gilchrist T, Doyle LW, Umstad MP. The Outcome of Monochorionic Diamniotic Twins Discordant at 11 to 13+6 Weeks' Gestation. Twin Res Hum Genet. 19(6):692-696, 2016 12. |
Observational-Dx |
89 cases |
To determine the ability of intertwin NT and crown rump length (CRL) discordances among monochorionic diamniotic (MCDA) twins to predict adverse outcomes. |
Of the 89 cases, 20 (22.5%) had at least one adverse outcome. NT discordance was more discriminatory of adverse outcome than was CRL discordance. The optimal values for predicting any adverse outcomes for NT were >23.7% and for CRL >3.5%. The positive predictive values for NT (52.4%) and CRL (29.8%) screening were relatively low; however, the lack of either NT or CRL discordances was more reassuring, with negative predictive values of 86.8% and 86.4%, respectively. |
4 |
| 40. Allaf MB, Vintzileos AM, Chavez MR, et al. First-trimester sonographic prediction of obstetric and neonatal outcomes in monochorionic diamniotic twin pregnancies. Journal of Ultrasound in Medicine. 33(1):135-40, 2014 Jan. |
Observational-Dx |
177 pregnancies |
To investigate whether discordant nuchal translucency and crown-rump length measurements in monochorionic diamniotic twins are predictive of adverse obstetric and neonatal outcomes. |
Fifty-four of the 177 pregnancies included (31%) had an adverse composite obstetric outcome, with TTTS in 19 (11%), IUGR in 21 (12%), discordant growth in14 (8%), IUFD in 14 (8%), and preterm birth before 28 weeks in 10 (6%). Of the 254 neonates included in the study, 69 (27%) were complicated by adverse composite neonatal outcomes, with respiratory distress syndrome being the most common (n = 59 [23%]). The areas under the curve for the combined discordances to predict composite obstetric and neonatal outcomes were 0.62 (95% confidence interval, 0.52–0.72), and 0.54 (95% confidence interval, 0.46–0.61), respectively. |
3 |
| 41. AIUM-ACR-ACOG-SMFM-SRU Practice Parameter for the Performance of Standard Diagnostic Obstetric Ultrasound Examinations. J Ultrasound Med 2018;37:E13-E24. |
Review/Other-Dx |
N/A |
To present a practice parameter for standard diagnostic obstetric ultrasound examination. |
No results stated in abstract. |
4 |
| 42. Rustico MA, Consonni D, Lanna M, et al. Selective intrauterine growth restriction in monochorionic twins: changing patterns in umbilical artery Doppler flow and outcomes. Ultrasound Obstet Gynecol. 49(3):387-393, 2017 Mar. |
Observational-Dx |
140 MCDA twins with sIUGR |
To describe changes in umbilical artery (UA) Doppler flow in monochorionic diamniotic (MCDA) twins affected by selective intrauterine growth restriction (sIUGR), to correlate Doppler findings with pregnancy course and perinatal outcome, and to report postnatal follow-up. |
At first examination, there were 65 cases with UA Doppler waveform pattern Type I, 62 with Type II and 13 with Type III. Of the 65 Type-I cases, 48 (74%) remained stable, while 17 (26%) changed to either Type II absent (14%), Type II reversed (9%) or Type III (3%). Of 62 Type-II cases (47 with absent and 15 with reversed flow), 33 (53%) remained stable (18 with absent and all 15 with reversed flow). The 29 Type-II absent cases which changed became Type II reversed (24/47, 51%) or Type III (5/47, 11%). All 13 Type-III cases remained stable. Compared with Type I, the risk of IUFD (adjusted for estimated fetal weight discordance and amniotic fluid deepest vertical pocket) was highest when the pregnancy was or became Type II reversed (HR, 9.5; 95% CI, 2.7-32.7) or Type II absent (HR, 4.3; 95% CI, 1.3-14.3). Mild neurological impairment was more prevalent in the IUGR twin than in the large cotwin (7% vs 1%, P = 0.02). |
3 |
| 43. Qureshey EJ, Quinones JN, Rochon M, Sarno A, Rust O. Comparison of management options for twin pregnancies with cervical shortening. J Matern Fetal Neonatal Med. 35(1):39-45, 2022 Jan. |
Review/Other-Dx |
64 pairs of twins |
To compare the effectiveness of expectant management (EM), cervical cerclage (CC) and vaginal progesterone (VP) in decreasing the rate of spontaneous preterm birth in twin gestations with midtrimester cervical shortening. |
Between January 2006 and July 2016, 64 pairs of twins with midtrimester cervical shortening were identified, 18 managed with EM (28.1%), 29 CC (45.3%), and 17 VP (26.6%), 52 of which had information regarding delivery outcomes. 90.4% of women delivered prematurely (<37 weeks). Women in the CC group were diagnosed with cervical shortening at a significantly earlier mean gestational age (CC 20.6 +/- 1.7 weeks versus EM 22.2 +/- 2.9 weeks and VP 22.2 +/- 2.0 weeks, p = .02) and had a shorter mean cervical length at the time of diagnosis (CC 1.18 +/- 0.7 cm vs. EM 1.56 +/- 0.7 and VP 1.95 +/- 0.6, p = .002), as compared to those in the EM and VP groups. There was no difference in gestational age at delivery (EM 30.9 +/- 5.2 weeks, CC 30.4 +/- 4.9 weeks and VP 32.4 +/- 4.1 weeks, respectively) or any of the secondary outcomes listed above. Women with a CL <1.5 cm delivered significantly earlier than those with a cervical length >/=1.5 cm (28.4 +/- 4.7 weeks vs. 33.2 +/- 3.6 weeks, p = .0001). After adjusting for potential confounders, cervical length <1.5 cm, not the management strategy, was the predictor of PTB before 32 weeks in this twin population [AOR 6.56 (95% CI 1.78, 24.20), p = .005]. |
4 |
| 44. McIntosh J, Feltovich H, Berghella V, Manuck T. The role of routine cervical length screening in selected high- and low-risk women for preterm birth prevention. Am J Obstet Gynecol 2016;215:B2-7. |
Review/Other-Dx |
N/A |
To review the indications and rationale for cervical length screening to prevent preterm birth in various clinical scenarios. |
No results stated in abstract. |
4 |
| 45. Nardozza LM, Simioni C, Garbato G, et al. Nomogram of fetal middle cerebral artery peak systolic velocity at 23-35 weeks of gestation in a Brazilian population: pilot study. J Matern Fetal Neonatal Med 2008;21:714-8. |
Review/Other-Dx |
90 healthy fetuses at between 23 and 35 weeks of gestation |
To establish normative data for the peak systolic velocity of the middle cerebral artery (MCA-PSV) of fetuses in the second half of pregnancy using multiples of the median and percentile reference range. |
There was a strong correlation between the MCA-PVS and gestational age (r = 0.70; p < 0.001). Values for the MCA-PSV for the following MoM were calculated: 1.0, 1.29, 1.50, and 1.55. The MCA-PSV 2.5(th) and 97.5(th) centiles ranged from 24.33 cm(2)/s to 78.36 cm(2)/s, respectively, between weeks 23 and 35. |
4 |
| 46. Vink J, Wapner R, D'Alton ME. Prenatal diagnosis in twin gestations. Semin Perinatol 2012;36:169-74. |
Review/Other-Dx |
N/A |
To discuss prenatal diagnosis in twin gestations. |
No results stated in abstract. |
4 |
| 47. Hubinont C, Lewi L, Bernard P, Marbaix E, Debieve F, Jauniaux E. Anomalies of the placenta and umbilical cord in twin gestations. Am J Obstet Gynecol 2015;213:S91-S102. |
Review/Other-Dx |
N/A |
To review the anomalies of the placenta and umbilical cord in twin gestations. |
No results stated in abstract. |
4 |
| 48. Roman A, Saccone G, Dude CM, et al. Midtrimester transvaginal ultrasound cervical length screening for spontaneous preterm birth in diamniotic twin pregnancies according to chorionicity. Eur J Obstet Gynecol Reprod Biol. 229:57-63, 2018 Oct. |
Observational-Dx |
580 women with diamniotic twin pregnancies |
To compare the mean transvaginal ultrasound (TVU) cervical length (CL) at midtrimester screening for spontaneous preterm birth in asymptomatic monochorionic diamniotic versus dichorionic diamniotic twin pregnancies |
580 women with diamniotic twin pregnancies underwent TVU CL screening between 18 0/6 and 23 6/7 weeks. 175 (30.2%) were monochorionic diamniotic pregnancies, and 405 (69.8%) were dichorionic pregnancies. The demographic characteristics were similar on both groups. The mean GA at TVU CL was about 20 week in both groups. The mean TVU CL was significantly lower in the monochorionic diamniotic (32.8 +/- 10.1) compared to the dichorionic (34.9 +/- 8.6) group (MD -2.10 mm, 95% CI -3.91 to -0.29). TVU CL </=30 mm was 16.6% (29/175) in the monochorionic group, and 11.9% (48/405) in the dichorionic group (aOR 1.48, 95% CI 1.03-2.43). Twins with a monochorionic diamniotic pregnancy had a significantly higher incidence of SPTB (53.1% vs 44.9%; aOR 1.22, 95% CI 1.22-1.79). For any given CL measured between 18 0-7 and 23 6/7 weeks, gestational age at delivery for monochorionic diamniotic pregnancies was about 2 weeks earlier compared to dichorionic pregnancies (MD -2.1 weeks; ANCOVA P < 0.001). |
3 |
| 49. Papathanasiou D, Witlox R, Oepkes D, Walther FJ, Bloemenkamp KW, Lopriore E. Monochorionic twins with ruptured vasa previa: double trouble! Fetal Diagn Ther 2010;28:48-50. |
Review/Other-Dx |
N/A |
To present a case of acute fetal distress in 2 fetuses in a monochorionic twin pregnancy caused by ruptured vasa previa that was not detected antenatally. |
No results stated in abstract. |
4 |
| 50. Nicholas L, Fischbein R, Aultman J, Ernst-Milner S. Dispelling Myths about Antenatal TAPS: A Call for Action for Routine MCA-PSV Doppler Screening in the United States. J Clin Med 2019;8:977. |
Review/Other-Dx |
N/A |
To dispell myths about antenatal TAPS. |
No results stated in abstract. |
4 |
| 51. Khalil A, Gordijn S, Ganzevoort W, et al. Consensus diagnostic criteria and monitoring of twin anemia-polycythemia sequence: Delphi procedure. Ultrasound Obstet Gynecol 2020;56:388-94. |
Review/Other-Dx |
N/A |
To determine, by expert consensus using a Delphi procedure, the key diagnostic features and optimal monitoring approach for TAPS. |
A total of 132 experts were approached. Fifty experts joined the first round, of whom 33 (66%) completed all three rounds. There was agreement that the monitoring interval for the development of TAPS should be every 2 weeks and that the severity should be assessed antenatally using a classification system based on middle cerebral artery (MCA) peak systolic velocity (PSV), but there was no agreement on the gestational age at which to start monitoring. Once the diagnosis of TAPS is made, monitoring should be scheduled weekly. For the antenatal diagnosis of TAPS, the combination of MCA-PSV >/= 1.5 MoM in the anemic twin and </= 0.8 MoM in the polycythemic twin was agreed. Alternatively, MCA-PSV discordance >/= 1 MoM can be used to diagnose TAPS. Postnatally, hemoglobin difference >/= 8 g/dL and intertwin reticulocyte ratio >/= 1.7 were agreed criteria for diagnosis of TAPS. There was no agreement on the cut-off of MCA-PSV or its discordance for prenatal intervention. The panel agreed on prioritizing perinatal and long-term survival outcomes in follow-up studies. |
4 |
| 52. Pettit KE, Merchant M, Machin GA, Tacy TA, Norton ME. Congenital heart defects in a large, unselected cohort of monochorionic twins. J Perinatol. 33(6):457-61, 2013 Jun. |
Review/Other-Dx |
926 monochorionic twins |
To determine the prevalence of congenital heart defects (CHDs) in a large, unselected cohort of monochorionic (MC) twins. |
A total of 926 liveborn MC twins met inclusion criteria. The prevalence of CHDs was 7.5%, 11.6 times the general population rate (CI 9.2 to 14.5). Septal defects were most common. 20% of infants with heart defects had twin-to-twin transfusion syndrome (TTTS) versus 8% of infants without defects (P<0.01); this association remained significant when controlling for potential confounders. |
4 |
| 53. Bahtiyar MO, Emery SP, Dashe JS, et al. The North American Fetal Therapy Network consensus statement: prenatal surveillance of uncomplicated monochorionic gestations. Obstet Gynecol. 125(1):118-123, 2015 Jan. |
Review/Other-Dx |
N/A |
To briefly describe complications of monochorionic gestations and to provide multidisciplinary, evidence-based, and consensus-driven recommendations for surveillance of uncomplicated monochorionic gestations. |
No results stated in abstract. |
4 |
| 54. Yonetani N, Ishii K, Kawamura H, Mabuchi A, Hayashi S, Mitsuda N. Significance of Velamentous Cord Insertion for Twin-Twin Transfusion Syndrome. Fetal Diagn Ther 2015;38:276-81. |
Review/Other-Dx |
357 twin pregnancies |
To evaluate the actual association between velamentous cord insertion (VCI) and twin-twin transfusion syndrome (TTTS) in the native cohort concerning the natural history of monochorionic twin pregnancies. |
A total of 357 monochorionic diamniotic twin pregnancies were analyzed. VCI in both twins was noted in 2.5% of cases and VCI in at least one twin was noted in 22.1% of cases. The incidence of TTTS was 8.4%; the incidence of a composite of adverse outcomes in at least one twin was 9.8%. There was no correlation between VCI and TTTS as well as a composite of adverse outcomes. |
4 |
| 55. Costa-Castro T, De Villiers S, Montenegro N, et al. Velamentous cord insertion in monochorionic twins with or without twin-twin transfusion syndrome: Does it matter? Placenta 2013;34:1053-8. |
Observational-Dx |
630 placentas |
To study the association between velamentous cord insertion (VCI) and different outcomes in monochorionic twins with and without twin-twin transfusion syndrome (TTTS). |
A total of 630 monochorionic placentas with TTTS (n = 304) and without TTTS (n = 326) were studied. The incidence of VCI in the TTTS and non-TTTS group was 36.8% and 35.9%, respectively (P = 0.886). The presence of VCI in one twin was significantly associated with small for gestational age (SGA) status (odds ratio [OR] 1.45, 95% CI 1.13, 1.87) and severe birth weight discordance (OR 3.09, 95% CI 1.93, 4.96). Our results also showed significant interaction between TTTS and VCI when we considered intrauterine fetal demise (IUFD) and gestational age (GA) at birth. The prevalence of IUFD in monochorionic pregnancies without TTTS increased from 4.6% to 14.1% in the presence of VCI (P = 0.027). In the TTTS group, the prevalence of IUFD was comparable in the absence or presence of VCI. Similarly, GA at birth was significantly lower in the presence of VCI only in the non-TTTS group. |
3 |
| 56. Couck I, Mourad Tawfic N, Deprest J, De Catte L, Devlieger R, Lewi L. Does site of cord insertion increase risk of adverse outcome, twin-to-twin transfusion syndrome and discordant growth in monochorionic twin pregnancy?. Ultrasound Obstet Gynecol. 52(3):385-389, 2018 Sep. |
Observational-Dx |
518 pregnancies |
To examine whether the sites of cord insertion, as determined on prenatal ultrasound examination, affect the risks of adverse outcome, twin-to-twin transfusion syndrome (TTTS) and discordant growth, and whether discordance in insertion sites or velamentous insertion in one or both twins best predicts risk. |
On univariate analysis, both discordant and velamentous insertions in one twin increased the risk of adverse outcome, TTTS and discordant growth. Intermediate insertion only increased the risk of discordant growth. Velamentous insertion in both twins increased the risk of adverse outcome and TTTS, but not of discordant growth. Multivariate logistic regression analysis showed velamentous insertion in one or both twins to independently predict adverse outcome and TTTS. For discordant growth, both intermediate/discordant and velamentous cord insertion in one twin were independent predictors. |
3 |
| 57. Saito M, Tokunaka M, Takita H, et al. Impact of first trimester determination of abnormal cord insertion on twin-to-twin transfusion syndrome and other adverse outcomes in monochorionic diamniotic twins: A retrospective cohort study. Prenat Diagn. 40(4):507-513, 2020 03. |
Observational-Dx |
109 MCDA twin pairs |
To assess the influence of abnormal cord insertion (CI) detected by first trimester ultrasonography on the development of twin-to-twin transfusion syndrome (TTTS) in monochorionic diamniotic (MCDA) twins. |
A total of 109 MCDA twin pairs were examined; 15 cases were classified into the abnormal CI group and 94 cases into the normal CI group. The incidence of TTTS was significantly higher in the abnormal than in the normal CI group (26.7% vs 7.45%, P = .04). In patients who developed TTTS, all donors had VCI. |
3 |
| 58. Jelin E, Hirose S, Rand L, et al. Perinatal outcome of conservative management versus fetal intervention for twin reversed arterial perfusion sequence with a small acardiac twin. Fetal Diagn Ther 2010;27:138-41. |
Observational-Dx |
76 patients |
To examine the outcomes of patients with twin reversed arterial perfusion (TRAP) sequence in which the acardiac twin was <or=50% the weight of the pump twin. |
Of the 18 patients with viable pregnancies that met the criteria for analysis, 7 (39%) underwent radiofrequency ablation (RFA) of the acardiac twin and 11 (61%) underwent conservative management. None of the pump twins in either group had hydrops fetalis. Three of the 11 acardiac twins in the conservative management group did not undergo RFA because they did not have blood flow at presentation to UCSF. Survival to delivery was 100% (7/7) in the RFA group and 91% (10/11) in the conservative management group. When we eliminated from our analysis the 3 pregnancies in the conservative management group without blood flow to the acardiac twin, survival to delivery was 88% (7/8). The single death occurred in 1 of the 3 monochorionic-monoamniotic pregnancies in the conservative management group, all of whom had blood flow to the acardiac twin. There were no statistically significant differences in gestational age at delivery, birth weight or survival between the RFA and conservative management groups, even after stratification by blood flow. |
3 |
| 59. Grantz KL, Grewal J, Albert PS, et al. Dichorionic twin trajectories: the NICHD Fetal Growth Studies. Am J Obstet Gynecol. 215(2):221.e1-221.e16, 2016 08. |
Observational-Dx |
171 patients |
To define the trajectory of fetal growth in dichorionic twins empirically using longitudinal 2-dimensional ultrasonography and to compare the fetal growth trajectories for dichorionic twins with those based on a growth standard that was developed by our group for singletons. |
Women underwent a median of 5 ultrasound scans. The 50th percentile abdominal circumference and estimated fetal weight trajectories of twin fetuses diverged significantly beginning at 32 weeks of gestation; biparietal diameter in twins was smaller from 34-36 weeks of gestation. There were no differences in head circumference or femur length. The mean head circumference/abdominal circumference ratio was progressively larger for twins compared with singletons beginning at 33 weeks of gestation, which indicated a comparatively asymmetric growth pattern. At 35 weeks of gestation, the average gestational age at delivery for twins, the estimated fetal weights for the 10th, 50th, and 90th percentiles were 1960, 2376, and 2879 g for dichorionic twins, respectively, and 2180, 2567, and 3022 g for the singletons, respectively. At 32 weeks of gestation, the initial week when the mean estimated fetal weight for twins was smaller than that of singletons, 34% of twins would be classified as small for gestational age with the use of a singleton, non-Hispanic white standard. By 35 weeks of gestation, 38% of twins would be classified as small for gestational age. |
3 |
| 60. Gabbay-Benziv R, Crimmins S, Contag SA. Reference Values for Sonographically Estimated Fetal Weight in Twin Gestations Stratified by Chorionicity: A Single Center Study. J Ultrasound Med. 36(4):793-798, 2017 Apr. |
Observational-Dx |
2115 twin pregnancies |
To determine reference values for sonography-based estimated fetal weight (EFW) in twin gestations in one single tertiary medical center in the United States. |
Values corresponding to the 5th, 10th, 50th, 90th, and 95th percentiles for EFW are presented for every gestational age. At 28, 32, and 36 weeks, values were as follows: 855, 1109, and 1363 g; 1351, 1732, and 2294 g; and 1363, 2112, and 2881 g for the 10th, 50th, and 90th percentiles, respectively. Chorionicity-specific curves are presented for comparison with previously published references. |
3 |
| 61. Wilkof Segev R, Gelman M, Maor-Sagie E, Shrim A, Hallak M, Gabbay-Benziv R. New reference values for biometrical measurements and sonographic estimated fetal weight in twin gestations and comparison to previous normograms. J Perinat Med. 47(7):757-764, 2019 Sep 25. |
Observational-Dx |
195 twin pregnancies at 22-39 gestational weeks |
To construct new reference values for biometrical measurements and sonographic estimated fetal weight (sEFW) in twin gestations and compare them to previously published normograms. |
Of them, 390 entered the primary analysis. The rest were left for validation. Seventy percent of the cohort were dichorionic-diamniotic twins (136/195), 16% (32/195) were monochorionic-diamniotic twins and three (1.5%) were monochorionic-monoamniotic twins. Twenty-four fetuses lacked data on chorionicity. The rest were monochorionic twins or were of unknown chorionicity. Values corresponding to the 2.5th, 10th, 50th, 90th and 97.5th percentiles for sEFW are presented for every GA. Validation by applying all 864 evaluations on constructed normograms was achieved. |
3 |
| 62. Kennelly MM, Sturgiss SN. Management of small-for-gestational-age twins with absent/reversed end diastolic flow in the umbilical artery: outcome of a policy of daily biophysical profile (BPP). Prenat Diagn 2007;27:77-80. |
Observational-Dx |
39 patients |
To evaluate a strategy of daily biophysical profile (BPP) for pregnancies with small-for-gestational-age twins and with absent or reversed end diastolic flow (AREDF) in the umbilical artery of one twin and to assess the latency interval between detection and delivery in monochorionic (MC) and dichorionic (DC) twin pregnancy. |
Twenty-two MC and 17 DC twin pregnancies were identified. There were no fetal losses in the viable actively monitored MC (19) and DC (13) twins. There was a longer latency interval in the MC group at 21.7 days versus 14.4 days in the DC group (p = 0.13). Delivery was indicated for an abnormal BPP (57.8% MC vs 30.8% DC). |
3 |
| 63. Booker W, Fox NS, Gupta S, et al. Antenatal Surveillance in Twin Pregnancies Using the Biophysical Profile. J Ultrasound Med 2015;34:2071-5. |
Observational-Dx |
539 twin pregnancies |
To report our experience with the sonographic portion of the biophysical profile in twin pregnancies as the primary screening modality. |
The incidence of IUFD per patient was 2 per 539 (0.4%; 95% confidence interval [CI], 0.1%-1.3%), and the incidence of IUFD per fetus was 2 per 1078 (0.19%; 95% CI, 0.05%-0.7%). The overall positive screen rate was 24 per 539 (4.45%; 95% CI, 3.0%-6.5%). The false-positive screen rate, defined as an abnormal biophysical profile that did not diagnose an IUFD or lead to delivery, was 10 per 539 (1.9%; 95% CI, 1.0%-3.4%). |
3 |
| 64. Emery SP, Bahtiyar MO, Moise KJ, North American Fetal Therapy N. The North American Fetal Therapy Network Consensus Statement: Management of Complicated Monochorionic Gestations. Obstet Gynecol 2015;126:575-84. |
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| 65. Jatzko B, Rittenschober-Bohm J, Mailath-Pokorny M, et al. Cerebral Lesions at Fetal Magnetic Resonance Imaging and Neurologic Outcome After Single Fetal Death in Monochorionic Twins. Twin Res Hum Genet. 18(5):606-12, 2015 Oct. |
Observational-Dx |
11 monochorionic twin pregnancies |
To evaluate the rate of cerebral lesions detected at fetal Magnetic Resonance Imaging (MRI) and to correlate the results with the neurologic outcome of the survivors of monochorionic twin pregnancies after sFD. |
Gestational age at sFD was 20.9 (+/-2.9) weeks; 55% (6/11) of survivors of monochorionic twin pregnancies after sFD showed cerebral lesions at fetal MRI; 72% (8/11) of all survivors had normal neonatal neurologic outcome: all survivors with normal fetal MRI and 50% of survivors with cerebral lesions at fetal MRI. Long-term neurologic assessment was normal in all tested patients with normal fetal MRI and in one of three tested patients with cerebral lesions at fetal MRI. |
3 |
| 66. Lanna MM, Consonni D, Faiola S, et al. Incidence of Cerebral Injury in Monochorionic Twin Survivors after Spontaneous Single Demise: Long-Term Outcome of a Large Cohort. Fetal Diagn Ther. 47(1):66-73, 2020. |
Observational-Dx |
78 pregnancies |
To evaluate incidence of cerebral injury and outcome in a large series of monochorionic (MC) twin survivors after spontaneous single fetal demise. |
Seventy-eight consecutive MC pregnancies were analyzed. Median gestational age (GA) at single fetal demise was 22 weeks (range 15-36); median interval between single demise and live birth was 105 days (range 1-175), with a median GA at birth of 36 weeks (range 23-41). Prenatal MR was performed in 57 of 78 cases (73%). Cerebral injury affected 14/78 (18%) co-twins, 2 of whom were born immediately after single demise, with postnatal diagnosis of cerebral injury; of the other 12 fetuses that were studied before birth, 10 had a prenatal diagnosis of lesion both with US and MR, one only with MR, and in one case, a grade III intraventricular hemorrhage was reported only after delivery, which occurred at 25 weeks, 5 weeks after the single demise. Signs of fetal anemia (MCA-PSV value above 1.55 MoM) were related to a higher risk of prenatal cerebral injury; cases with postnatal diagnosis of lesion were delivered at lower GA. |
3 |
| 67. Conte G, Righini A, Griffiths PD, et al. Brain-injured Survivors of Monochorionic Twin Pregnancies Complicated by Single Intrauterine Death: MR Findings in a Multicenter Study. Radiology. 288(2):582-590, 2018 08. |
Observational-Dx |
42 surviving MC twins |
To describe and classify the range of brain injuries present at prenatal, in-utero magnetic resonance (MR) imaging in co-twin survivors of monochorionic (MC) twin pregnancies complicated by single intrauterine death (SIUD). |
The primary distinction of brain abnormalities was into nonfocal and focal lesions. The nonfocal lesions included periventricular leukomalacia (group 1; two fetuses), generalized encephalomalacia (group 2; nine fetuses), posterior encephalomalacia (group 3; seven fetuses), and bilateral parasagittal and perisylvian injury (group 4; three fetuses). The focal lesions included nonhemorrhagic lesions (group 5; 14 fetuses) and hemorrhagic lesions (group 6; seven fetuses). Focal brain lesions were more likely to be found in the surviving MC pregnancies complicated by twin-twin transfusion syndrome (TTTS) (odds ratio, 2.4; 95% confidence interval: 1.3, 18.5; P = .01) and in fetuses that underwent an obstetric intervention (odds ratio, 2.8; 95% confidence interval: 1.8, 23.6; P = .006). |
3 |
| 68. Kocaoglu M, Kline-Fath BM, Calvo-Garcia MA, Zhang B, Nagaraj UD. Magnetic resonance imaging of the fetal brain in monochorionic diamniotic twin gestation: correlation of cerebral injury with ultrasound staging and survival outcomes. Pediatr Radiol. 50(8):1131-1138, 2020 07. |
Observational-Dx |
34 pregnancies |
To assess the incidence of cerebral damage on fetal MRI and correlate abnormal cerebral diffusion-weighted imaging (DWI) findings with survival outcome and the ultrasound staging of TTTS. |
Thirty-four pregnancies (68 fetuses) with 42 fetal cerebral abnormalities were identified by MRI/DWI alone. Of these 42 fetal cerebral abnormalities, 33 fetal brain lesions were visible only on DWI (n=25 donor, n=8 recipients; n=30 unilateral, n=3 bilateral; n=26 diffuse, n=7 focal). Quintero staging in these 34 pregnancies was as follows: 9 Stage I, 7 Stage II, 13 Stage III, 4 Stage IV, 1 Stage V. There was no significant correlation between the presence of cerebral infarction or hemorrhage using MRI/DWI and ultrasound staging (P=0.138). The overall survival rate was 63.2% (43/68). There was a significant correlation between the presence of cerebral infarction or hemorrhage on MRI/DWI and delivery status (P=0.009). |
3 |
| 69. De Paepe ME, Luks FI. What-and why-the pathologist should know about twin-to-twin transfusion syndrome. Pediatr Dev Pathol 2013;16:237-51. |
Review/Other-Dx |
N/A |
To summarize the current knowledge of the placental contributions to TTTS and other complications of monochorionic twinning and describe the strengths and limitations of placental examination in these settings |
No results stated in abstract. |
4 |
| 70. Quintero RA. Twin-twin transfusion syndrome. Clin Perinatol 2003;30:591-600. |
Review/Other-Dx |
N/A |
To discuss and review twin-twin transfusion syndrome. |
No results stated in abstract. |
4 |
| 71. Zaretsky MV, Tong S, Lagueux M, et al. North American Fetal Therapy Network: Timing of and indications for delivery following laser ablation for twin-twin transfusion syndrome. Am J Obstet Gynecol MFM 2019;1:74-81. |
Observational-Dx |
847 pregnancies |
To investigate the indications and factors influencing the timing of delivery following laser treatment, we collected delivery information regarding twin-twin transfusion syndrome cases in a large multicenter cohort. |
After laser, the average latency to delivery was 10.11 +/- 4.8 weeks and the mean gestational age at delivery was 30.7 +/- 4.5 weeks. Primary maternal indications for delivery comprised 79% of cases. The leading indications included spontaneous labor (46.8%), premature rupture of membranes (17.1%), and placental abruption (8.4%). Primary fetal indications accounted for 21% of cases and the most frequent indications included donor non-reassuring status (20.5%), abnormal donor Dopplers (15.1%), and donor growth restriction (14.5%). The most common secondary indications for delivery were premature rupture of membranes, spontaneous labor and donor growth restriction. Multivariate modeling found gestational age at diagnosis, stage, history of prior amnioreduction, cerclage, interwin membrane disruption, procedure complications and chorioamniotic membrane separation as predictors for both gestational age at delivery and latency. |
3 |
| 72. Tollenaar LSA, Lopriore E, Middeldorp JM, et al. Improved prediction of twin anemia-polycythemia sequence by delta middle cerebral artery peak systolic velocity: new antenatal classification system. Ultrasound Obstet Gynecol. 53(6):788-793, 2019 Jun. |
Observational-Dx |
45 uncomplicated and 35 TAPS monochorionic twin pregnancies |
To investigate the diagnostic accuracy of delta middle cerebral artery peak systolic velocity (MCA-PSV) > 0.5 multiples of the median (MoM) and compare its predictive value with that of the current MCA-PSV cut-off values of > 1.5 MoM in the donor and < 1.0 MoM in the recipient, for the diagnosis of twin anemia-polycythemia sequence (TAPS) in monochorionic twin pregnancy. |
In total, 45 uncomplicated and 35 TAPS monochorionic twin pregnancies were analyzed. The sensitivity and specificity of the cut-off MCA-PSV values (donor > 1.5 MoM, recipient < 1.0 MoM) to predict TAPS was 46% (95% CI, 30-62%) and 100% (95% CI, 92-100%), respectively; positive predictive value was 100% (95% CI, 81-100%) and negative predictive value 70% (95% CI, 58-80%). Delta MCA-PSV showed a sensitivity of 83% (95% CI, 67-92%) and a specificity of 100% (95% CI, 92-100%); the positive and negative predictive values were 100% (95% CI, 88-100%) and 88% (95% CI, 77-94%), respectively. Of the 35 cases with TAPS diagnosed postnatally, 13 twin pairs showed a delta MCA-PSV > 0.5 MoM but did not fulfill the cut-off MCA-PSV criteria. Of these 13 TAPS twins, nine donors and four recipients had normal MCA-PSV values. There was a high correlation between delta MCA-PSV and intertwin difference in hemoglobin level (R = 0.725, P < 0.01). |
3 |
| 73. Tavares de Sousa M, Fonseca A, Hecher K. Role of fetal intertwin difference in middle cerebral artery peak systolic velocity in predicting neonatal twin anemia-polycythemia sequence. Ultrasound Obstet Gynecol. 53(6):794-797, 2019 Jun. |
Observational-Dx |
154 MC twin pregnancies |
To evaluate the relationship between the fetal intertwin difference in middle cerebral artery peak systolic velocity (MCA-PSV) and intertwin difference in hemoglobin (Hb) concentration at birth in monochorionic diamniotic (MCDA) twin pregnancies in order to assess its potential role in the prediction of twin anemia-polycythemia sequence (TAPS). |
A total of 154 out of 256 MC twin pregnancies fulfilled the inclusion criteria. Fetal intertwin difference in MCA-PSV MoM correlated positively with neonatal intertwin difference in Hb concentration (r = 0.79; P < 0.001). The 90(th) centile for intertwin difference in Hb was 7.25 g/dL. There were 15 (9.7%) cases with a Hb difference >/= 7.25 g/dL at birth. ROC curve analysis showed a high accuracy of fetal intertwin MCA-PSV MoM difference for the prediction of neonatal intertwin Hb difference >/= 7.25 g/dL at birth (area under the ROC curve, 0.976 (95% CI, 0.935-0.993); P = 0.012). The optimal cut-off for intertwin MCA-PSV MoM difference was 0.373, with a sensitivity of 93.3% (95% CI, 68.1-99.8%) and a specificity of 95.7% (95% CI, 90.8-98.4%). The positive predictive value was 70% (95% CI, 45.7-88.1%) and the negative predictive value was 99.3% (95% CI, 95.9-100%). |
3 |
| 74. Trieu NT, Weingertner AS, Guerra F, et al. Evaluation of the measurement of the middle cerebral artery peak systolic velocity before and after placental laser coagulation in twin-to-twin transfusion syndrome. Prenat Diagn. 32(2):127-30, 2012 Feb. |
Review/Other-Dx |
N/A |
To evaluate the incidence of elevated middle cerebral artery peak systolic velocity (MCA-PSV) in twin-to-twin transfusion syndrome (TTTS) before and after laser and its predictive value for intrauterine fetal death (IUFD) occurring within 2 to 7 days following laser. |
The incidence of elevated MCA-PSV prior to and following laser (NS) was 8.2% to 9.7% (non significant (NS)). There was no correlation between the incidence of an elevated MCA-PSV prior to laser and fetal survival up to 7 days after laser (NS, chi(2) :3.49). In contrast, the presence of an MCA-PSV above 1.5 MoM 48 h following laser in the former donor puts the former donor at a higher risk for IUFD within a week after surgery [odds ratio (OR):3.42 (interval of confidence (IC) 95%:1.9-30.6), chi(2) :8.68, p < 0.003]. |
4 |
| 75. Batsry L, Matatyahu N, Avnet H, et al. Perinatal outcome of monochorionic diamniotic twin pregnancy complicated by selective intrauterine growth restriction according to umbilical artery Doppler flow pattern: single-center study using strict fetal surveillance protocol. Ultrasound Obstet Gynecol. 57(5):748-755, 2021 05. |
Observational-Dx |
88 MCDA twin pregnancies |
To determine the perinatal outcome of monochorionic diamniotic (MCDA) twin pregnancies complicated by selective intrauterine growth restriction (sIUGR), which were classified according to the umbilical artery (UA) Doppler flow pattern of the IUGR twin. |
In 26 (43.3%) cases in the expectant-management group, the classification according to the UA Doppler flow pattern changed during gestation, resulting in 26 (43.3%) cases of Type-I, 22 (36.7%) cases of Type-II and 12 (20.0%) cases of Type-III sIUGR at the final examination. The perinatal survival rate of both twins with sIUGR Types I, II and III at the final examination was 100%, 81.8% and 75.0%, respectively (P = 0.04). Two cases of double fetal death and one case of single fetal death occurred 1-4 weeks after the Doppler pattern had changed from Type I or Type II to Type III. The median GA at delivery was 34.8 (IQR, 33.1-35.7) weeks in Type I, 30.3 (IQR, 28.6-32.1) weeks in Type II and 32.0 (IQR, 31.3-32.6) weeks in Type III (P < 0.01). The total intact survival rate was 100% for Type I, 77.3% for Type II and 75.0% for Type III (P < 0.001). Multivariate analysis demonstrated that early GA at diagnosis (odds ratio (OR), 0.83 (95% CI, 0.69-0.99); P = 0.04) and the presence of Type II or III vs Type I at the last examination (OR, 13.16 (95% CI, 1.53-113.32); P = 0.02) were associated with preterm birth < 32 weeks' gestation. Early GA at diagnosis was also associated with the composite adverse outcome (OR, 0.60 (95% CI, 0.36-0.99); P = 0.04). |
3 |
| 76. Weisz B, Hogen L, Yinon Y, et al. Perinatal outcome of monochorionic twins with selective IUGR compared with uncomplicated monochorionic twins. Twin Res Hum Genet 2011;14:457-62. |
Observational-Dx |
128 twin pregnancies |
To evaluate the perinatal outcome of MC twins with selective IUGR (sIUGR). |
Neonatal outcome of fetuses complicated with sIUGR and normal Doppler was similar to controls. Neonates born to pregnancies complicated by sIUGR and abnormal Doppler had significantly increased incidence of CNS findings, RDS, NEC, sepsis, and neonatal death compared to controls. Adverse outcome in this group was independently associated only with gestational age at birth. |
3 |
| 77. Ishii K, Murakoshi T, Hayashi S, et al. Ultrasound predictors of mortality in monochorionic twins with selective intrauterine growth restriction. Ultrasound Obstet Gynecol 2011;37:22-6. |
Observational-Dx |
101 twin pregnancies |
To evaluate the use of ultrasound assessment to predict risk of mortality in expectantly managed monochorionic twin fetuses with selective intrauterine growth restriction (sIUGR). |
Of 101 sIUGR twins, 22 (21.8%) fetuses suffered intrauterine demise and nine (8.9%) suffered neonatal death; 70 (69.3%) survived the neonatal period. Multiple logistic regression analysis revealed that the stuck twin phenomenon (odds ratio (OR): 14.5; 95% CI: 2.2–93.2; P = 0.006) and constantly absent diastolic flow in the umbilical artery (OR: 29.4; 95% CI: 3.3–264.0; P = 0.003) were significant risk factors for mortality. |
3 |
| 78. Zanardini C, Prefumo F, Fichera A, Botteri E, Frusca T. Fetal cardiac parameters for prediction of twin-to-twin transfusion syndrome. Ultrasound Obstet Gynecol 2014;44:434-40. |
Observational-Dx |
100 pregnancies |
To assess myocardial performance index measured by conventional Doppler (MPI) and by tissue Doppler imaging (MPI') at 18 weeks' gestation in monochorionic diamniotic twins for the prediction of twin-to-twin transfusion syndrome (TTTS). |
Of the 100 pregnancies, 88 were controls (84 uncomplicated and four developed sIUGR) and 12 developed TTTS. Right ventricule (RV)-MPI and left ventricule (LV)-MPI, and LV-MPI' were significantly higher in future TTTS recipients than in controls, while RV-MPI' was significantly lower in donors. RV-MPI and LV-MPI were found to be predictive indicators in pregnancies that had not yet developed TTTS. Their negative predictive values were > 90%, and their specificities > 80%. The best performing index was LV-MPI', with a sensitivity of 91.7% and specificity of 88.6%. |
3 |
| 79. Habli M, Michelfelder E, Cnota J, et al. Prevalence and progression of recipient-twin cardiomyopathy in early-stage twin-twin transfusion syndrome. Ultrasound Obstet Gynecol. 39(1):63-8, 2012 Jan. |
Observational-Dx |
123 patients |
To describe the prevalence, severity, incidence and rate of progression of recipient-twin cardiomyopathy in Stages I and II TTTS. |
Seventy-seven of 123 (62.6%) cases were Quintero Stage I and 46/123 (37.4%) Quintero Stage II. Eighty (65.0%) were upstaged to Cincinnati Stage IIIA (n = 25), IIIB (n = 23) or IIIC (n = 32). Management included observation in 11 (8.9%), amnioreduction in 26 (21.1%), amnioreduction followed by selective fetoscopic laser photocoagulation (SFLP) in 43 (35.0%) and primary SFLP in 43 (35.0%). Of 80 cases managed by observation or amnioreduction initially, 43 (53.8%) progressed within a mean duration of 1.4 +/- 1.5 weeks. The incidence of progression increased significantly as degree of recipient-twin cardiomyopathy at presentation worsened: Stage I, 9/27 (33.3%); Stage II, 8/15 (53.3%); Stage IIIA, 8/16 (50.0%); Stage IIIB, 10/10 (100%); and Stage IIIC, 8/12 (66.7%) (chi(2) = 14, P < 0.01). Overall fetal survival was 205 out of 244 (84.0%). Fetal survival with observation only was 81.8% (18/22), with amnioreduction only it was 92.3% (48/52), with initial observation or amnioreduction followed by SFLP it was 86.9% (73/84) and with primary SFLP it was 76.7% (66/86). |
3 |
| 80. Finneran MM, Pickens R, Templin M, Stephenson CD. Impact of recipient twin preoperative myocardial performance index in twin-twin transfusion syndrome treated with laser. J Matern Fetal Neonatal Med. 30(7):767-771, 2017 Apr. |
Observational-Dx |
43 patients |
To validate the efficacy of laser therapy for twin-twin transfusion syndrome (TTTS) in the treatment of recipient twin cardiomyopathy and investigate whether severity of preoperative cardiomyopathy can predict fetal survival postoperatively. |
There was a substantial improvement in recipient LV (0.57 +/- 0.13 versus 0.43 +/- 0.13, p </= 0.0001) and RV (0.60 +/- 0.16 versus 0.49 +/- 0.18, p </= 0.0001) MPI postoperatively (median = 8 days). Recipient preoperative LV and RV MPI did not correlate with recipient or donor survival at 24 hours, 7 days or at birth. Thirty-seven recipients (95%) showed improvement in either LV or RV MPI and 22 (56%) showed complete resolution of cardiac dysfunction. |
3 |
| 81. Van Mieghem T, Martin AM, Weber R, et al. Fetal cardiac function in recipient twins undergoing fetoscopic laser ablation of placental anastomoses for Stage IV twin-twin transfusion syndrome. Ultrasound Obstet Gynecol. 42(1):64-9, 2013 Jul. |
Observational-Dx |
22 patients |
To document the severity of fetal cardiac dysfunction in Stage IV TTTS (fetal hydrops) and assess evolution of cardiac function longitudinally after fetoscopic laser surgery. |
Nineteen fetuses (86.4%) had ascites, eight (36.4%) had pleural effusions, nine (40.9%) had a pericardial effusion and 12 (54.5%) had subcutaneous edema at presentation. Preoperatively, cardiac function was grossly abnormal in all. Eight fetuses (36.4%) had functional pulmonary atresia and one (4.5%) had functional aortic atresia. Seventy-seven percent of recipient fetuses survived until birth. Postoperative echocardiographic follow-up (mean, 26 days) showed that indices of fetal cardiac function improved considerably, but never completely normalized. Six of the eight fetuses with functional pulmonary atresia (75.0%), as well as the fetus with functional aortic atresia, survived to birth. In all cases, the functional atresia resolved within 48 h of laser ablation therapy and none had structural valve anomalies at birth. All fetal effusions resolved after the laser. |
3 |
| 82. Delabaere A, Leduc F, Reboul Q, et al. Prediction of neonatal outcome of TTTS by fetal heart and Doppler ultrasound parameters before and after laser treatment. Prenat Diagn. 36(13):1199-1205, 2016 Dec. |
Observational-Dx |
106 patients |
To determine the prognostic value of fetal Doppler and echocardiographic parameters for neonatal survival up to 30 days after laser coagulation in monochorionic pregnancies complicated by twin-twin transfusion syndrome (TTTS). |
The final analysis was limited to cases with ultrasound within 2 days before laser (n = 77) and 4 weeks after laser (n = 86). Overall neonatal survival rate was 64.9% (135/208) and 77.9% of pregnancies (81/104) had at least one baby alive. For the recipient twin, the preoperative predictors of neonatal survival were umbilical artery (UA) pulsatility index (PI), cerebro-placental PI ratio, UA end diastolic flow (EDF), ductus venosus a-wave, right ventricular myocardial performance index (RV-MPI) and CHOP score. The postoperative predictors of donor survival were donor RV-MPI and recipient UA EDF, umbilical vein pulsations, tricuspid regurgitation, cardiac hypertrophy and CHOP score. |
3 |
| 83. Khalil A, Beune I, Hecher K, et al. Consensus definition and essential reporting parameters of selective fetal growth restriction in twin pregnancy: a Delphi procedure. Ultrasound Obstet Gynecol. 53(1):47-54, 2019 Jan. |
Review/Other-Dx |
N/A |
To determine, by expert consensus using a Delphi procedure, the key diagnostic features of and the essential reporting parameters in sFGR. |
A total of 72 experts were approached, of whom 60 agreed to participate and entered the first round; 48 (80%) completed all four rounds. For the definition of sFGR irrespective of chorionicity, one solitary parameter (estimated fetal weight (EFW) of one twin < 3(rd) centile) was agreed. For monochorionic twin pregnancy, at least two out of four contributory parameters (EFW of one twin < 10(th) centile, abdominal circumference of one twin < 10(th) centile, EFW discordance of >/= 25%, and umbilical artery pulsatility index of the smaller twin > 95(th) centile) were agreed. For sFGR in dichorionic twin pregnancy, at least two out of three contributory parameters (EFW of one twin < 10(th) centile, EFW discordance of >/= 25%, and umbilical artery pulsatility index of the smaller twin > 95(th) centile) were agreed. |
4 |
| 84. Chaveeva P, Poon LC, Sotiriadis A, Kosinski P, Nicolaides KH. Optimal method and timing of intrauterine intervention in twin reversed arterial perfusion sequence: case study and meta-analysis. Fetal Diagn Ther 2014;35:267-79. |
Meta-analysis |
N/A |
To define the optimal method and timing of intervention in twin reversed arterial perfusion (TRAP) sequence. |
A variety of techniques were used to interrupt the blood supply to the acardiac twin. Most procedures were performed at or after 16 weeks, and with most methods the survival rate of the pump twin was about 80%. Good results were also obtained for triplet pregnancies. In 18 of 30 cases (60%) diagnosed at 11-14 weeks, there was spontaneous cessation of flow in the acardiac twin before planned intervention at 16-18 weeks, and in 11 of these (61.1%) the pump twin died or suffered brain damage. In 103 pregnancies treated by intrafetal laser at 12-27 weeks, there was no correlation between gestational age at treatment and survival rate, but there was an inverse association between gestational age at treatment and gestational age at birth. |
M |
| 85. American College of Radiology. ACR–SPR Practice Parameter for the Safe and Optimal Performance of Fetal Magnetic Resonance Imaging (MRI). Available at: https://www.acr.org/-/media/ACR/Files/Practice-Parameters/mr-fetal.pdf |
Review/Other-Dx |
N/A |
To promote safe and optimal performance of fetal magnetic resonance imaging (MRI). |
No abstract available. |
4 |
| 86. American College of Radiology. ACR-ACOG-AIUM-SMFM-SRU Practice Parameter for the Performance of Standard Diagnostic Obstetrical Ultrasound. Available at: https://www.acr.org/-/media/ACR/Files/Practice-Parameters/us-ob.pdf |
Review/Other-Dx |
N/A |
To promote the safe and effective use of diagnostic and therapeutic radiology by describing the key elements of standard ultrasound examinations in the first, second, and third trimesters of pregnancy. |
No abstract available. |
4 |
| 87. American College of Radiology. ACR Committee on MR Safety. 2024 ACR Manual on MR Safety. Available at: https://www.acr.org/-/media/ACR/Files/Radiology-Safety/MR-Safety/Manual-on-MR-Safety.pdf. |
Review/Other-Dx |
N/A |
Guidance document to promote the use of magnetic resonance (MR) safe practices. |
No abstract available. |
4 |
| 88. American College of Radiology. ACR Appropriateness Criteria® Radiation Dose Assessment Introduction. Available at: https://www.acr.org/-/media/ACR/Files/Appropriateness-Criteria/RadiationDoseAssessmentIntro.pdf. |
Review/Other-Dx |
N/A |
To provide evidence-based guidelines on exposure of patients to ionizing radiation. |
No abstract available. |
4 |
