The Effect of Gestational Age on the Outcomes of Term Pregnancies

This study was designed to analyze the outcomes of labor in uncomplicated, singleton pregnancies with reliable gestational age having their deliveries between 37-42 weeks. Using a cohort study, 206 women having their deliveries after 256-280 days of gesiation (37-40 weeks) were compared with 185 women having their deliveries after 281-294 days of gestation (40-42 weeks) who were admitted in Shohada, Hazrat Zeinab (SA) and Mahdieh Hospitals. The main variables analyzed were the meconium stained aminionic fluid, apgar score, fetal distress, labor induction, method of delivery, shoulder dystocia, and macrosomia. Meconium stained amnionic fluid (15.3% vs 10.2%, P=0.000), nduction of labor (40.4% vs 18% P=0.000), cesarean section (27.2% vs 15%, P=0.000) instrumental delivery (3.2% vs 0.48% (P=0.000) were found to be significantly higher in the 40-42 weeks group compared to the 3740 week group. Fetal distress (10.27% vs 5.8%) apgar score less than 7 in 5 and 10 minutes (0.6%vs 0.4%, P>0.05) were not significantly different in the two groups. There were no macrosomia, shoulder dystocia and stillbirth in the both groups. Maternal age and parity did not alter the risk of post date pregnancies, even though the history of post date pregnancy is a risk factor for post date pregnancy.