Placental abruption in twin pregnancies, risk factors and perinatal outcomes

Objective
To investigate risk factors and pregnancy outcome of patients with twin pregnancies complicated with placental abruption.

Study Design
A retrospective population-based study was conducted, comparing twin pregnancies with and without placental abruption, delivered during the years 1988 to 2014. Stratified analysis using multiple logistic regression models was performed to control for confounders.

Results
During the study period there were 5,266 twin deliveries, of which 108 (2.1%) had placental abruption. The following conditions were significantly associated with placental abruption in twins: advanced maternal age, high parity, fertility treatments, second trimester bleeding, premature rupture of membranes (PROM) and earlier gestational age (Table). Patients with placental abruption were more likely to have cesarean deliveries, as well as to receive blood transfusion. Placental abruption was significantly associated with adverse perinatal outcomes such as very low birth weight, Apgar scores < 7 at 5 min and perinatal mortality (Table). Using backward stepwise multiple logistic regression analysis with perinatal mortality as the outcome variable, controlling for gestational age, fertility treatment and PROM, placental abruption was noted as an independent risk factor for perinatal mortality (adjusted OR 1,83, 95% CI 1.05-3.21; p=0.03).

Conclusion
In twin pregnancies, advanced maternal age, high parity, fertility treatments, second trimester bleeding and premature rupture of membranes are significant risk factors for placental abruption. Furthermore, placental abruption in twin pregnancies is an independent risk factor for perinatal mortality.