Is fetal gender significant in the perinatal outcome of pregnancies complicated by placental abruption?

Seventy cases of placental abruption were studied. These occurred in 12,800 deliveries, an incidence of 4.8 per 1000. There were more female infants (34-56%) compared with males (27-44%). Sixteen infants were stillborn and one baby died in the neonatal period. Thirteen of the perinatal deaths occurred in male infants. We speculate that a higher metabolic rate in male infants may account for this sex difference.