Fetal gender and gestational-age-related incidence of pre-eclampsia.

Background: Male fetal gender is associated with an overall increased risk of pre-eclampsia. However, it was recently shown that the male: female birth ratio was decreased in pre-eclampsia associated with preterm delivery. The reason for this discrepancy is not known.

Umbilical cord levels of interleukin-1 receptor antagonist and neonatal outcome.

Background: Previous studies indicate that there may be infant gender differences in cytokine expression associated with differences in neonatal morbidity.

Objective: We tested the hypothesis that umbilical cord interleukin-1 receptor antagonist (IL-1ra) correlates with infant gender and neonatal outcome in preterm infants.

Study Design: IL-1ra was measured in cord blood taken from 58 preterm infants (33 males, 25 females) with gestational age less than 32 weeks.