Accuracy of Prenatal Ultrasound in Detecting Growth Abnormalities in Triplets: A Retrospective Cohort Study

Perinatal outcome of monochorionic triamniotic triplet pregnancy: multicenter cohort study

OBJECTIVE

Monochorionic (MC) triplet pregnancies are extremely rare and information on these pregnancies and their complications is limited. We aimed to investigate the risk of early and late pregnancy complications, perinatal outcome and the timing and methods of fetal intervention in these pregnancies.

METHODS

This was a multicenter retrospective cohort study of MC triamniotic (TA) triplet pregnancies managed in 21 participating centers around the world from 2007 onwards. Data on maternal age, mode of conception, diagnosis of major fetal structural anomalies or aneuploidy, gestational age (GA) at diagnosis of anomalies, twin-to-twin transfusion syndrome (TTTS), twin anemia-polycythemia sequence (TAPS), twin reversed arterial perfusion (TRAP) sequence and or selective fetal growth restriction (sFGR) were retrieved from patient records. Data on antenatal interventions were collected, including data on selective fetal reduction (three to two or three to one), laser surgery and any other active fetal intervention (including amniodrainage). Data on perinatal outcome were collected, including numbers of live birth, intrauterine demise, neonatal death, perinatal death and termination of fetus or pregnancy (TOP). Neonatal data such as GA at birth, birth weight, admission to neonatal intensive care unit and neonatal morbidity were also collected. Perinatal outcomes were assessed according to whether the pregnancy was managed expectantly or underwent fetal intervention.

RESULTS

Of an initial cohort of 174 MCTA triplet pregnancies, 11 underwent early TOP, three had an early miscarriage, six were lost to follow-up and one was ongoing at the time of writing. Thus, the study cohort included 153 pregnancies, of which the majority (92.8%) were managed expectantly. The incidence of pregnancy affected by one or more fetal structural abnormality was 13.7% (21/153) and that of TRAP sequence was 5.2% (8/153). The most common antenatal complication related to chorionicity was TTTS, which affected just over one quarter (27.6%; 42/152, after removing a pregnancy with TOP < 24 weeks for fetal anomalies) of the pregnancies, followed by sFGR (16.4%; 25/152), while TAPS (spontaneous or post TTTS with or without laser treatment) occurred in only 4.6% (7/152) of pregnancies. No monochorionicity-related antenatal complication was recorded in 49.3% (75/152) of pregnancies. Survival was apparently associated largely with the development of these complications: there was at least one survivor beyond the neonatal period in 85.1% (57/67) of pregnancies without antenatal complications, in 100% (25/25) of those complicated by sFGR and in 47.6% (20/42) of those complicated by TTTS. The overall rate of preterm birth prior to 28 weeks was 14.5% (18/124) and that prior to 32 weeks' gestation was 49.2% (61/124).

CONCLUSION

Monochorionicity-related complications, which can impact adversely perinatal outcome, occur in almost half of MCTA triplet pregnancies, creating a challenge with regard to counseling, surveillance and management. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Diagnostic Value and High-Risk Factors of Two-Dimensional Ultrasonography Combined with Four-Dimensional Ultrasonography in Prenatal Ultrasound Screening of Fetal Congenital Malformations

Objective. This study mainly analyzes the diagnostic value of two-dimensional ultrasonography (2D-US) combined with four-dimensional ultrasonography (4D-US) in prenatal ultrasound screening of fetal congenital malformations (CMs) and explores the high-risk factors affecting fetal malformations. Methods. The clinical and imaging data of 2247 pregnant women who underwent prenatal fetal malformation screening in the General Hospital of Ningxia Medical University between February 2020 and October 2021 were collected and analyzed, retrospectively. All pregnant women underwent 2D-US, and those with suspected fetal malformations were further inspected by 4D-US. The accuracy of ultrasound examination results relative to actual pregnancy outcomes was analyzed, taking the neonatal malformation after induced labor or actual delivery as the gold standard, and the risk factors influencing the occurrence of fetal malformations were discussed. Results. A total of 87 cases (3.87%) of fetal malformations were detected out of the 2247 parturients examined. The accuracy, sensitivity, and specificity of 2D-US diagnosis were 81.40%, 43.68%, and 82.92%, respectively, while the data were 83.67%, 51.72%, and 84.95% for 4D-US, respectively, and 93.59%, 90.80%, and 93.70%, respectively, for 2D-US +4D-US. The combined diagnosis of 2D-US +4D-US achieved statistically higher accuracy, sensitivity, and specificity than either of them alone. One-way analysis of variance and multivariate logistic regression analysis identified that the independent risk factors affecting fetal malformation were $\text{age}\ge 35$ , history of adverse pregnancy and childbirth, medication during pregnancy, toxic exposure during pregnancy, and history of seropositive for TORCH-IgM. Folic acid supplementation was a protective factor. Conclusions. Prenatal US is an effective approach for screening fetal malformations. 2D-US +4D-US can effectively improve the diagnostic rate of fetal malformations. For pregnant women with high-risk factors, prevention should be given priority, and prenatal screening and prenatal diagnosis should be standardized to reduce the occurrence of fetal malformations.

The mystery of monozygotic twinning II: What can monozygotic twinning tell us about Amyoplasia from a review of the various mechanisms and types of monozygotic twinning?

Monozygotic (MZ) twins ("identical twins") are essentially unique to human beings. Why and how they arise is not known. This article reviews the possible different types of MZ twinning recognized in the previous article on twins and arthrogryposis. There appear to be at least three subgroups of MZ twinning: spontaneous, familial, and those related to artificial reproductive technologies. Each is likely to have different etiologies and different secondary findings. Spontaneous MZ twinning may relate to "overripe ova." Amyoplasia, a specific nongenetic form of arthrogryposis, appears to occur in spontaneous MZ twinning and may be related to twin-twin transfusion.

Prognostic Value of Doppler Ultrasound in Triplets Conceived by In Vitro Fertilization: A Case Report and Review of the Literature

Umbilical artery Doppler ultrasound-which informs on maternal-fetal-placental blood flow-may be the most valuable surveillance tool in triplet pregnancies, crucial to diagnose early fetal growth restriction. To illustrate the prognostic value of Doppler ultrasound and launch a discussion of its role in multiple gestational, high-risk pregnancy, we present the case of a 42-year-old woman with trichorionic triamniotic triplet pregnancy conceived by in vitro fertilization, who showed early signs of poor outcome for one of the triplets via umbilical artery Doppler by the 23rd week and middle cerebral artery Doppler by the 29th week of gestation.

Prevalence of Gestational Diabetes in Triplet Pregnancies: A Retrospective Cohort Study and Meta-Analysis

Background: Over the last decades, there has been a substantial increase in the incidence of higher-order multiple gestations. Twin pregnancies are associated with an increased risk of gestational diabetes mellitus (GDM). The literature on GDM rates in triplet pregnancies is scarce. Methods: A retrospective cohort study was performed to assess the prevalence of GDM in women with a triplet pregnancy. GDM was defined through an abnormal oral glucose tolerance test (OGTT). A meta-analysis of GDM prevalence was also carried out. Results: A cohort of 60 women was included in the analysis. Of these, 19 (31.7%) were diagnosed with GDM. There were no differences in pregnancy outcomes between women with and without GDM. In the meta-analysis of 12 studies, which used a sound GDM definition, an estimated pooled prevalence of 12.4% (95% confidence interval: 6.9–19.1%) was found. In a leave-one-out sensitivity analysis, the estimated GDM prevalence ranged from 10.7% to 14.1%. Conclusion: The rate of GDM seems increased in women with triplets compared to singleton pregnancies. However, GDM did not impact short-term pregnancy outcomes.

Reliability of sonographic fetal weight estimation in triplet pregnancies: a retrospective cohort study

PURPOSE

To review our experience in ultrasound fetal weight estimation in our large population of triplet pregnancies.

METHODS

Ninety-seven triplet pregnancies were retrospectively included between January 2003 and January 2017. Sonographic fetal weight estimation using Hadlock's and Schild's formulas was compared to actual birth weight in a tertiary-care center in Vienna, Austria. Statistical analyses were performed using a stepwise linear regression model and crosstabs.

RESULTS

The median discrepancy between the sonographically estimated fetal weight by Hadlock's formula and the actual birth weight was 106 g (IQR 56-190). The percentage error and its standard deviation were - 2.5 ± 12.1%, and the median percentage error was - 3.6%. Concerning the use of Hadlock's formula, estimated fetal weight was the most important factor predictive of actual birth weight with an estimate of 0.920 (p < 0.001). Female neonates had been overestimated by a mean of 50.473 g per fetus. The sonographic prediction of small-for-gestational-age neonates was significantly reliable (p < 0.001), with positive and negative predictive values ranging from 81.3 to 100.0%. Similar results were obtained for Schild's formula.

CONCLUSION

Even if sonographically estimated fetal weight in triplet pregnancies has a high overall accuracy of fetal weight estimation, there are some limitations in prediction of intrauterine growth restrictions, especially in female fetuses.