• cesarean delivery;
  • gestational age;
  • risk factor;
  • second twin


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 ≥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 ≥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 ≥39 weeks.