[Late preterms: the influence of foetal gender on neonatal outcome]

The group of the so-called late preterms (infants born at 34 0/7-36 6/7 weeks gestational age) has been underestimated with respect to their neonatal outcome. Among infants born before the 29th week of pregnancy, a gender-specific difference in favour of females regarding morbidity became evident. The aim of this study is to investigate whether these findings are transferable to the group of late preterms.

The neonatal outcome of 528 consecutive singletons, born at 34 0/7-36 6/7 weeks gestational age and requiring intensive care, was examined.

Neonatal complications have been particularly analysed with regard to gender-specific differences. Boys (n=292) were significantly more frequently affected by sepsis (3.8 vs. 0.9%; p=0,0314, x²-test). Girls had significantly longer stays in the neonatal intensive care unit (median 12 (Q1:8; Q3:17) vs. 11 (6;16) days; p=0.0149, t-test). In a multiple logistic regression model, male gender and premature rupture of membranes were borderline significant with respect to the occurrence of sepsis - boys had a 4.4-fold risk (OR=0.228 [95% CI: 0.050-1.041]; p=0.0564) and premature rupture of membranes had a 3.5-fold risk (OR=3.462 [0.938-12.779]; p=0.0623). Strong cause variables for the length of stay in the neonatal intensive care unit were birth weight, gestational age and premature rupture of membranes after adjustment.

The influence of foetal gender on the neonatal outcome in the late preterm group (34 0/7-36 6/7 gestational age) has been relativised.