External Cephalic Version in Twin Pregnancies with Non-Vertex Presenting Twin.

Abstract

Objective Mode of delivery in twin pregnancies is primarily based on the presentation of the leading twin¹. When the leading twin is vertex, the recommendation is to attempt vaginal delivery, otherwise the recommended mode of delivery is cesarean delivery (CD)². In singleton pregnancies, external cephalic version (ECV) is a widely accepted procedure for non-vertex presentation, with a success rate of 50-70%³. However, there is limited data on the safety and success of ECV in twin pregnancies⁴. Thus, the goal of our study was to assess success rates of ECVs in twin pregnancies with a non-vertex leading twin as well as safety and rates of subsequent vaginal deliveries, in a prospective clinical trial and to further evaluate whether ECV influences the mode of delivery and associated maternal and neonatal outcomes. Study Design This was a prospective interventional trial with a historical control group conducted at a large tertiary medical center. The study included women with (DCDA) twin pregnancy with a non-vertex presenting twin, who were at a gestational age ≥ 37+0 weeks at the time of the planned elective CD or ECV, were 18 years or older, multiparous, with no previous CD and no contraindication for vaginal delivery. After obtaining informed consent, ECVs were performed in a controlled setting, in an operating room, under combined spinal-epidural anesthesia (CSE) by two obstetricians experienced in ECVs. Women with successful ECV underwent immediate induction of Labor (IOL), while those with unsuccessful ECV proceeded directly to CD. Maternal and neonatal outcomes of study participants were compared to an historical comparison group, retrospectively identified among women with DCDA twin pregnancies and similar characteristics, who were scheduled to undergo a planned elective CD. The primary outcome of the study was a composite adverse maternal and neonatal outcome. Secondary outcomes measured included individual maternal and neonatal adverse outcomes. A secondary analysis was conducted on the study group to identify factors associated with successful ECV in this group. Results A total of 55 women who met inclusion criteria agreed to undergo an ECV attempt (Study group). Of these, 4 (7.2%) had spontaneous onset of labor before scheduled ECV and underwent urgent CD. Of the remaining 51 women, twenty-nine (56.8%) had a successful ECV attempt and of these 25 (86.2%) had a successful vaginal delivery of both twins, while 22 (43.2%) had failed ECV attempt and underwent immediate CD. Maternal and neonatal characteristics of the study and control groups were similar (Table 1). There was no difference in rate of the composite adverse maternal & neonatal outcome between the groups (23.1% vs. 20%. P-value=0.69) (Table 2). CD rates were 54 % vs. 100% in the study and control group, respectively (P-value<0.01). There was no increase in maternal or neonatal adverse outcomes between the groups. Length of stay was significantly shorter in the study group (3.5±1.9vs. 4.3±1.7 days, P-value=0.02). In a secondary analysis, no significant factors were identified as predictors of successful ECV. Three major adverse events occurred during the study period. One participant had severe postpartum abdominal pain and another a rectus sheath hematoma. One of the neonates had a femoral fracture. Conclusion This study represents the largest trial to date on the use of ECV in DCDA twin pregnancies. We found that ECV was successful in approximately 50% of attempts and that 45% of all women having an ECV attempt achieved successful vaginal delivery. While ECV was not free of complications it did not increase the rate of maternal or neonatal adverse outcomes as compared to the control group.