Planned cesarean or vaginal delivery for women in spontaneous labor with a twin pregnancy: A secondary analysis of the Twin Birth Study.

The Twin Birth Study, a multicenter randomized controlled trial, found no differences in neonatal outcomes in women with twins randomized to planned cesarean or vaginal delivery. Nevertheless, women who present in spontaneous labor might expect a better outcome following a trial of vaginal delivery than undergoing cesarean delivery. In this secondary analysis, we aimed to compare neonatal outcomes of women who presented in spontaneous labor in the two arms of the Twin Birth Study. Women in whom the first twin was in the cephalic presentation were randomized between 32 + 0 and 38 + 6 weeks to planned vaginal delivery or cesarean. The primary outcome was a composite of fetal or neonatal death or serious neonatal morbidity. Of the 2804 women included in the Twin Birth Study, 823 women in the planned vaginal delivery arm and 612 in the planned cesarean arm presented in spontaneous labor. Although the odds ratio favored planned vaginal delivery, there was no statistically significant difference in the rate of primary outcome between the vaginal delivery and cesarean arms (1.8% vs 2.7%, respectively; P = 0.16; OR 1.49; 95% CI, 0.87-2.55). Similarly, the rates of the individual components of the primary outcome and of maternal adverse outcome were similar between the two arms. In women with twins who present in spontaneous labor between 32 + 0 and 38 + 6 weeks' gestation, where the first twin is cephalic, a policy of planned vaginal delivery or cesarean is not associated with significant differences in neonatal or maternal outcomes.

Mei-Dan E ，Dougan C ，Melamed N ，Asztalos EV ，Aviram A ，Willan AR ，Barrett JFR ... -  《-》

Delivery of monochorionic twins: lessons learned from the Twin Birth Study.

The current literature regarding the recommended mode of delivery of monochorionic-diamniotic twins is limited to small numbers, retrospective studies, and comparisons of outcomes of monochorionic-diamniotic twin pregnancies with those of dichorionic-diamniotic twin pregnancies instead of outcomes of trial of labor vs elective cesarean delivery of monochorionic-diamniotic twins. This study aimed to compare perinatal and maternal outcomes of planned cesarean delivery and planned vaginal delivery of monochorionic-diamniotic twins using the Twin Birth Study data. This study is a secondary analysis of the Twin Birth Study. Women were randomized from 32 weeks and 0 days gestation to 38 weeks and 6 days gestation to planned cesarean delivery or planned vaginal delivery. Twin A in the cephalic presentation and estimated weight of each twin between 1500 and 4000 grams were the inclusion criteria. Pregnancies complicated by fetal reduction after 13 weeks of gestation, lethal fetal anomaly, or contraindication to vaginal delivery were excluded. Elective delivery was planned between 37 weeks and 5 to 7 days of gestation and 38 weeks and 6 to 7 days of gestation. Perinatal and maternal outcomes of monochorionic-diamniotic twin pregnancies were compared between those randomized for planned cesarean delivery and those randomized for planned vaginal delivery. In addition, outcomes of monochorionic-diamniotic twin pregnancies were compared with those of dichorionic-diamniotic twin pregnancies. Out of the 1393 women in each arm, 346 (24.9%) women in the planned cesarean delivery arm and 324 (23.3%) women in the planned vaginal delivery arm had monochorionic-diamniotic twin pregnancies and were eligible for the first analysis. The rate of cesarean delivery was 39.2% in the planned vaginal delivery arm and was 91.3% in the planned cesarean delivery arm. There was no significant difference in gestational age at delivery between the groups (34.4±1.8 weeks vs 34.5±1.8 weeks; P=.78). No difference was found in maternal outcomes. As for perinatal outcomes, the rate of the primary adverse neonatal composite outcomes in twins A or twins B was similar in both the planned vaginal delivery and the planned cesarean delivery arms (twins A, 1.2% vs 1.2% [P=.92]; twins B, 1.2% vs 3.2% [P=.09]). Within the planned cesarean delivery arm, the rate of primary adverse neonatal composite outcome was higher in twins B than twins A (3.2% vs 1.2%; P=.03). There was no difference in the primary adverse neonatal composite outcome between twins A in the monochorionic-diamniotic group and the dichorionic-diamniotic group (1.2% vs 1.3%; P=.89) or between twins B in similar groups (2.3% vs 2.7%; P=.47). In monochorionic-diamniotic twin pregnancy between 32 weeks and 0 to 7 days of gestation and 38 weeks and 6 to 7 days of gestation, with twin A in a cephalic presentation, planned cesarean delivery did not decrease or increase the risk of fetal or neonatal death or serious neonatal morbidity, as compared with planned vaginal delivery.

Aviram A ，Lipworth H ，Asztalos EV ，Mei-Dan E ，Melamed N ，Cao X ，Zaltz A ，Hvidman L ，Barrett JFR ... -  《-》

Cesarean delivery or induction of labor in pre-labor twin gestations: a secondary analysis of the twin birth study.

Dougan C ，Gotha L ，Melamed N ，Aviram A ，Asztalos EV ，Anabusi S ，Willan AR ，Barrett J ，Mei-Dan E ... -  《-》

Planned Cesarean or planned vaginal delivery for twins: secondary analysis of randomized controlled trial.

To evaluate whether there is a differential benefit of planned Cesarean delivery (CD) over planned vaginal delivery (VD) in women with a twin pregnancy and the first twin in cephalic presentation, depending on prespecified baseline maternal and pregnancy characteristics, and/or gestational age (GA) at delivery. This was a secondary analysis of the Twin Birth Study, which included 2804 women with a twin pregnancy and the first twin (Twin A) in cephalic presentation between 32 + 0 and 38 + 6 weeks' gestation at 106 centers in 25 countries. Women were assigned randomly to either planned CD or planned VD. The main outcome measure was composite adverse perinatal outcome, defined as the occurrence of perinatal mortality or serious neonatal morbidity in at least one twin. The baseline maternal and pregnancy characteristics (markers) considered were maternal age, parity, history of CD, use of antenatal corticosteroids, estimated fetal weight (EFW) of Twin A, EFW of Twin B, > 25% difference in EFW between the twins, presentation of Twin B, chorionicity on ultrasound, method of conception, complications of pregnancy, ruptured membranes at randomization and GA at randomization. Separate logistic regression models were developed for each marker in order to model composite adverse perinatal outcome as a function of the specific marker, planned delivery mode and the interaction between these two terms. In addition, multivariable logistic regression analysis with backward variable elimination was performed separately in each arm of the trial. The association between planned mode of delivery and composite adverse perinatal outcome, according to GA at delivery, was assessed using logistic regression analysis. Of the 2804 women initially randomized, 1391 were included in each study arm. None of the studied baseline markers was associated with a differential benefit of planned CD over planned VD in the rate of composite adverse perinatal outcome. GA at delivery was associated differentially with composite adverse perinatal outcome in the treatment arms (P for interaction < 0.001). Among pregnancies delivered at 32 + 0 to 36 + 6 weeks, there was a trend towards a lower rate of composite adverse perinatal outcome in those in the planned-VD group compared with those in planned-CD group (29 (2.2%) vs 48 (3.6%) cases; odds ratio (OR) 0.62 (95% CI, 0.37-1.03)). In pregnancies delivered at or after 37 + 0 weeks, planned VD was associated with a significantly higher rate of composite adverse perinatal outcome, as compared with planned CD (23 (1.5%) vs 10 (0.7%) cases; OR, 2.25 (95% CI, 1.06-4.77)). The perinatal outcome of twin pregnancies with the first twin in cephalic presentation may differ depending on GA at delivery and planned mode of delivery. At 32-37 weeks, planned VD seems to be favorable, while, from around 37 weeks onwards, planned CD might be safer. The absolute risks of adverse perinatal outcomes at term are low and must be weighed against the increased maternal risks associated with planned CD. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Zafarmand MH ，Goossens SMTA ，Tajik P ，Bossuyt PMM ，Asztalos EV ，Gardener GJ ，Willan AR ，Roumen FJME ，Mol BW ，Barrett YJ ，Twin Birth Study Collaborative Group ... -  《-》

A randomized trial of planned cesarean or vaginal delivery for twin pregnancy.

Barrett JF ，Hannah ME ，Hutton EK ，Willan AR ，Allen AC ，Armson BA ，Gafni A ，Joseph KS ，Mason D ，Ohlsson A ，Ross S ，Sanchez JJ ，Asztalos EV ，Twin Birth Study Collaborative Group ... -  《-》