Perinatal Outcome of Second Twin with Respect to Mode of Delivery: An Observational Study

Introduction: With the advent of assisted reproductive techniques, multi-fetal pregnancies are on the rise. While caesarean section is the defined mode of delivery for triplets and higher order pregnancies, the picture for twin delivery is not so clear. While a trial for vaginal delivery is attempted, the second twin is considered vulnerable to complications. Whether this translates into worsened perinatal outcomes is not well defined. Aim: To study the perinatal outcome and to identify the various factors influencing the perinatal outcome of second twin with respect to mode of delivery. Materials and Methods: Data was collected from hospital birth records regarding the mode of delivery of viable twins (period of gestation >28 weeks) and outcome of second twin with respect to APGAR scores, NICU stay, neonatal morbidity and mortality, over a period of 12 months. Results: Of the 93 pairs of twins delivered, in 21(22.6%) pregnancies both twins were delivered vaginally, in 70(75.2%) pregnancies both were delivered by caesarean section and in 2 (1.8%) pregnancies 1st twin was delivered by vaginal route and 2nd by caesarean. In the vaginal delivery group, 85.7% times both twins were in vertex position. In the caesarean group, vertex/non-vertex (38.57%) was the most common presentation followed by non-vertex /non-vertex (25.71%) and vertex/vertex (24.28%). Comparing the perinatal outcome of second twin in both groups, the odds for APGAR score <= 7 was 3.385 times (OR-3.384, 95% CI 1.2099-9.4684, p=0.02) in the vaginal group compared to the caesarean group. There was no association (OR-1.054, 95% CI 0.3344-3.3268, p=0.9) between neonatal morbidity of second twin compared to mode of delivery. All 3 perinatal deaths were in the vaginal group (all between 28-32 weeks of gestation). Conclusion: There is an increased preference for caesarean delivery in twin pregnancies except in cases where both the twins are in vertex position and not associated with any other maternal or fetal complication. However, the caesarean mode of delivery does not influence neonatal morbidity in second twin, except when the 1 minute APGAR score is <= 7.