Risk factors for postpartum hemorrhage requiring transfusion in cesarean deliveries for Japanese twins: comparison with those for singletons.

Objective: The aim of this study was to identify the factors associated with the increased risk of postpartum hemorrhage requiring transfusion in Japanese twin pregnancies in comparison with those in Japanese singleton pregnancies.

Methods: We reviewed the obstetric records of all singleton and twin deliveries after 22 weeks' gestation at the Japanese Red Cross Katsushika Maternity Hospital from 2003 through 2011. Potential risk factors for transfusion due to hemorrhage after cesarean delivery were selected according to previous studies of postpartum hemorrhage or transfusion or both after delivery: maternal age, parity, previous cesarean deliveries, history of infertility therapies such as in vitro fertilization, gestational age at delivery, neonatal birth weight, placenta previa, uterine myoma≥6 cm, hypertensive disorders, placental abruption, emergency cesarean deliveries and general anesthesia.

Results: Using multiple logistic regression, the independent risk factors for postpartum hemorrhage requiring transfusion in singleton pregnancies were preterm delivery [odds ratio (OR) 2.40, 95% confidence interval (CI) 1.2-4.6, p<0.01], placenta previa (OR 8.08, 95% CI 3.9-16, p<0.01) and placental abruption (OR 12.8, 95% CI 2.3-76, p<0.01). In twin pregnancies, however, the independent risk factors for postpartum hemorrhage requiring transfusion were gestational age at ≥41 weeks (OR 8.20, 95% CI 1.3-40, p<0.01) and hypertensive disorders (OR 5.45, 95% CI 2.2-14, p<0.01).

Conclusions: The factors associated with postpartum hemorrhage requiring transfusion in cesarean deliveries of twins seemed to be different from those in singleton cesarean deliveries.