Tiran Dias

Crown–rump length discordance and adverse perinatal outcome in twins: analysis of the Southwest Thames Obstetric Research Collaborative (STORK) multiple pregnancy cohort

Evidence for the role of first‐trimester ultrasound in predicting outcome in twin pregnancies is conflicting. The aim of this study was to determine the association between crown–rump length (CRL) discordance and adverse perinatal outcome in twin pregnancies.

Early fetal loss in monochorionic and dichorionic twin pregnancies: analysis of the Southwest Thames Obstetric Research Collaborative (STORK) multiple pregnancy cohort.

Monochorionic (MC) twins are at increased risk of early fetal loss secondary to vascular complications such as twin–twin transfusion syndrome (TTTS). This study compared the early perinatal loss rates between MC and dichorionic (DC) twins in an era of invasive treatment for TTTS.

Screening for pre‐eclampsia by using changes in uterine artery Doppler indices with advancing gestation

The aim of the study was to assess the relationship of changes in uterine artery (UtA) Doppler pulsatility indices (PI) between first and second trimesters and the subsequent development of pre‐eclampsia.

Ultrasound estimation of birth weight in twin pregnancy: comparison of biometry algorithms in the STORK multiple pregnancy cohort

The aims of this study were first, to ascertain the accuracy of formulae for ultrasonographic birth‐weight estimation in twin compared with singleton pregnancies and second, to assess the accuracy of sonographic examination in the prediction of birth‐weight discordance in twin pregnancies.

Does antenatal ultrasound labeling predict birth order in twin pregnancies

It is often assumed by obstetricians, neonatologists and parents that the prenatal nomenclature used to identify twins on ultrasound is consistent with twin labeling after their birth. The aim of this study was to use a large regional database of twin ultrasound scans to validate the effectiveness of a scan before delivery in predicting twin birth‐order.

Twin pregnancy chorionicity determination in a tertiary care setting

Ultrasound determination of chorionicity is most reliable before 14 weeks and subsequently reduces in accuracy with advancing gestation. The aim of this study was to evaluate the accuracy of chorionicity determination in a birth cohort of twin pregnancies. Antenatal ultrasound determination of chorionicity in twin pregnancy was undertaken at suboptimal period of gestation in over twothirds of twin pregnancies. Even in the first trimester of pregnancy, the accuracy of chorionicity determination was lower than previously reported.

The influence of chorionicity and gestational age at single fetal loss on the risk of preterm birth in twin pregnancies: analysis of the STORK multiple pregnancy cohort

Single intrauterine death (sIUD) in twin pregnancy is associated with a significant risk of cotwin demise and preterm birth (PTB), especially in monochorionic (MC) twins. However, it is yet to be established whether the gestational age at loss may influence the pregnancy outcome. The aim of this study was to explore the risk of PTB according to the gestational age at diagnosis of sIUD.

Monoamniotic twin pregnancy

Key content n nMonoamniotic twins are believed to account for 1–5% of all monozygotic conceptions, with an estimated annual incidence of 30–150 pregnancies in the UK. nHigh perinatal loss rates in monoamniotic twins have been attributed mainly to umbilical cord entanglement, inter-twin transfusion syndrome, discordant fetal abnormality or fetal growth restriction. nManagement of monoamniotic twin pregnancy is aimed at preventing antenatal fetal death and optimising timing of delivery. nDespite the paucity of robust data on the incidence and causes of perinatal loss, elective delivery at 32–34 weeks of gestation has been proposed. nMost obstetric units use caesarean birth as the preferred mode of delivery for monoamniotic twins to prevent intrapartum cord complications. n n n n nLearning objectives n nTo understand the aetiology, incidence and diagnosis of monoamnionicity. nTo be able to identify the type and prevalence of complications in monoamniotic twins. nTo be aware of the current evidence on the antenatal management and optimal timing of delivery of monoamniotic twin pregnancy. n n n n nEthical issues n nCan we justify elective preterm delivery and its subsequent complications without a robust evidence base demonstrating a reduction in perinatal morbidity and mortality?Monoamniotic twins are believed to account for 1–5% of all monozygotic conceptions, with an estimated annual incidence of 30–150 pregnancies in the UK. High perinatal loss rates in monoamniotic twins have been attributed mainly to umbilical cord entanglement, inter‐twin transfusion syndrome, discordant fetal abnormality or fetal growth restriction. Management of monoamniotic twin pregnancy is aimed at preventing antenatal fetal death and optimising timing of delivery. Despite the paucity of robust data on the incidence and causes of perinatal loss, elective delivery at 32–34 weeks of gestation has been proposed. Most obstetric units use caesarean birth as the preferred mode of delivery for monoamniotic twins to prevent intrapartum cord complications.

OP31.09: Systematic labelling of twin pregnancies on ultrasound: limitations and guidance

were reviewed in twin pregnancies. Twin pregnancies were divided into spontaneous and ART. Results: Among the 196 twin pregnancies studied, 72 were obtained with ART (63% by IVF, 19.4% ICSI and 16.6% IUI). Women from ART showed a statistically difference in age (median 35 years old, 32–39 P = 0.001) and parity (P < 0.0001). There were no statistically significant differences of gender and obstetric diseases (gestational diabetes, hypertension and pre-eclampsia) among the ART and non-ART. In 97.4% caesarean section was performed for programming assistance (66.5%), selective growth restriction (10%) and maternal disease (10.5%) and other reasons (13%), with the same distribution between the two groups. Five vaginal deliveries (2.6%) occurred. The infants were 136 in the ART group, 245 in non-ART. They were comparable for birth weight, length and Apgar at 5 minutes. Conversely, there were a higher number of female in non ART group (P = 0.04) and ART group presented a gestational age at birth less than the non-ART group (P < 0.05) Conclusions: Spontaneous and ART twin pregnancies does not differ in pregnancy complications and neonatal outcome.

OC09.03: Systematic review of monochorionic versus dichorionic twin pregnancy losses near term

the last 10 years. Chorionicity and indication for invasive testing were retrieved from the clinical notes. The following outcomes were analysed: fetal loss within 4 weeks from the procedure and < 24 weeks’ gestation; preterm premature rupture of membranes (PPROM) within 4 weeks from the procedure and < 34 weeks’ gestation; spontaneous preterm delivery (PTD) < 32 weeks of gestation. Results: A total of 267 twin pregnancies underwent invasive prenatal diagnosis during the study period, 212 dichorionic diamniotic and 55 monochorionic diamniotic. Amniocentesis was the most frequent procedure in both groups. Indications for invasive testing, type of procedure used, and pregnancy outcomes are described in Table 1 and reported with their 95% confidence intervals. Conclusions: We observed a fetal loss rate < 24 weeks of 1.5% (95% CI, 0.3–4.3). As expected, monochorionic pregnancies had a higher incidence of adverse pregnancy outcome.