Objective: To identify neonatal complications associated with placenta previa.
Methods: This was a population-based, retrospective cohort study involving all singleton deliveries in Nova Scotia from 1988 to 1995. The study group consisted of all completed singleton pregnancies complicated by placenta previa; all other singleton pregnancies were considered controls. Patient information was collected from the Nova Scotia Atlee perinatal database. Neonatal complications were evaluated while controlling for potential confounders. The data were analyzed using χ2, Fisher exact test, and multiple logistic regression.
Results: Among 92,983 pregnancies delivered during the study period, 305 cases of placenta previa were identified (0.33%). After controlling for potential confounders, neonatal complications significantly associated with placenta previa included major congenital anomalies (odds ratio [OR] 2.48), respiratory distress syndrome (OR 4.94), and anemia (OR 2.65). The perinatal mortality rate associated with placenta previa was 2.30% (compared with 0.78% in controls) and was explained by gestational age at delivery, occurrence of congenital anomalies, and maternal age. Although there was a higher rate of preterm births in the placenta previa group (46.56% versus 7.27%), there was no difference in birth weights between groups after controlling for gestational age at delivery.
Conclusion: Neonatal complications of placenta previa included preterm birth, congenital anomalies, respiratory distress syndrome, and anemia. There was no increased occurrence of fetal growth restriction.
Placenta previa, an important cause of antepartum hemorrhage, is estimated to occur in 0.31% to 0.60% of pregnancies at delivery.1–14 Previous studies of complications of placenta previa might have limited current relevance. Almost all studies were conducted more than a decade ago.1–9,11,13–19 Although expectant obstetric treatment has not changed since then, there have been improvements in diagnosis20–22 and neonatal treatment.23,24 Those refinements might have changed the rate of neonatal complications. Previous studies examined women from individual centers, introducing possible referral bias. Some of those studies used birth certificate data or survey data,4,10 limiting the available variables. Even when important variables were included, most studies did not take into account the potential effects of confounding factors.1–3,5–8,14–19 The objective of this study was to determine the neonatal complications of placenta previa.