Placental abruption, offspring sex, and birth outcomes in a large cohort of mothers.

OBJECTIVE: To investigate stillbirth, neonatal, and perinatal death outcomes in pregnancies complicated by placental abruption, according to fetal sex. METHODS: We utilized maternally linked cohort data files of singleton live births to mothers diagnosed with placental abruption during the period 1989 through 2005 (n = 10,014). Logistic regression models were employed to generate adjusted odd ratios and their 95% confidence intervals. Male babies served as the referent category. RESULTS: The sex ratio at birth was 1.18. The overall prevalence of stillbirth, neonatal mortality, and perinatal mortality was 7.2%, 4.5%, and 11.8%, respectively. Placental abruption was less likely to occur in mothers carrying female pregnancies than mothers of male infants (adjusted odds ratio [95% confidence interval] = 0.89 [0.86-0.93]). There were no significant sex differences with regards to stillbirth, neonatal mortality, and perinatal mortality. Similar findings were observed for preterm and term infants. CONCLUSIONS: Although a preponderance of male infants was discernable among mothers with placental abruption, no sex difference in fetal survival was observed among the offspring of the mothers affected by placental abruption.