Aim: A case-control study of twins was performed to identify clinical predictions of emergency cesarean delivery in the second-born twin after vaginal delivery of the first twin.
Methods: The obstetric records were reviewed of all twin vaginal deliveries at the Japanese Red Cross Katsushika Maternity Hospital from 2002 through 2007.
Results: There were 206 vaginal deliveries of first twins at >or=33 weeks of gestation. Of these deliveries, nine women (4.4%) underwent an emergency cesarean for the delivery of the second twin. The incidence of cesarean delivery for the second twin was significantly greater in cases with a history of infertility therapy (odds ratio: 5.0, 95% confidence intervals: 1.2-22), gestational age at >or=39 weeks (24, 4.7-120), nonvertex presentation (6.2, 1.5-26), operative delivery of the first twin (6.1, 1.5-24) and intertwin delivery time interval >30 min (7.2, 1.7-30).
Conclusion: The most important risk factor of emergency cesarean delivery in the second twin was a gestational age of >or=39 weeks.