Optimal gestational age for twin delivery

We evaluated the timing of twin delivery associated with perinatal outcome in gestations of at least 36 completed weeks.

This was a retrospective analysis of infant and maternal hospital records for a consecutive series of twin deliveries at New York Hospital-Cornell Medical Center. The inclusion criteria were delivery after 36 weeks' gestation during a 7-year period (1987 to 1993), without congenital anomalies or early fetal demise. Adverse perinatal outcomes were compared between deliveries before 38 weeks' gestational age and those at or after 38 weeks' gestation.

Of 776 twin deliveries during the study period, 329 met the inclusion criteria. Adverse perinatal outcome was significantly higher among the twin pregnancies that delivered before 38 weeks' gestation compared with those that delivered at or after 38 weeks' gestation. Twin pregnancies that delivered between 36 and 37 weeks' gestation were 13 times more likely to require neonatal intensive care compared with those who delivered at or after 38 weeks' gestation (95% confidence interval 1.8 to 95.9; p < 0.001).

In uncomplicated twin gestations, delivery at between 36 and 37 weeks' gestation was not associated with a reduction in neonatal complications compared with deliveries at or after 38 weeks' gestation.