Combined Effect of Fetal Sex and Advanced Maternal Age on Pregnancy Outcomes

BACKGROUND Fetal sex and maternal age are each known to affect outcomes of pregnancies. The objective of the present study was to investigate the influence of the combination of maternal age and fetal sex on pregnancy outcomes in term and post-term singleton pregnancies. MATERIAL AND METHODS This was a retrospective study on term singleton pregnancies delivered between 2004 and 2008 at the Chaim Sheba Medical Center. Data collected included maternal age, fetal sex, and maternal and neonatal complications. The combined effect of fetal sex and maternal age on complications of pregnancy was assessed by multivariable logistic regression models. RESULTS The study population comprised 37,327 pregnancies. The risk of operative deliveries increased with maternal age ≥ 40 and in pregnancies with male fetuses. The risk of maternal diabetes and of longer hospitalization increased as maternal age increased, and in women ≥ 40 carrying male fetuses. The risk of hypertensive disorders increased in pregnancies with males as maternal age advanced. The risk of shoulder dystocia and neonatal respiratory complications increased in male neonates born to women<40. The risk of neonatal hypoglycemia increased in males for all maternal ages. CONCLUSIONS Risk assessment for fetal sex and advanced maternal age were given for different pregnancy complications. Knowledge of fetal sex adds value to the risk assessment of pregnancies as maternal age increases.