Background: Advanced maternal age is an important predictor for maternal and neonatal outcomes such as
maternal mortality, low birth weight, stillbirth, preterm birth, cesarean section and preeclampsia.
Objective: To determine the association of advanced maternal age and adverse maternal and neonatal outcomes in Iranian
Methods: In this hospital-based cross-sectional study, 5117 pregnant women from 103 hospitals in Tehran, Iran, were
participated in the study in 2015. The required data were gathered from hospitals which equipped to the department of
obstetrics and gynecology. Advanced maternal age was considered as an independent variable and unwanted pregnancy,
preeclampsia, preterm birth, cesarean section and low birth weight were considered as interested outcomes.
Results: In our study, the prevalence of advanced maternal age was 12.08%. Advanced maternal age was significantly
associated with higher risk of unwanted pregnancy (OR: 1.39, 95% CI: 1.12-1.73), preterm birth (OR: 1.75, 95% CI: 1.28-
2.39) and cesarean section (OR: 1.34, 95% CI: 1.03-1.74). In our study, there was no significant relationship between
advanced maternal age and preeclampsia but this relationship could be clinically important (OR: 1.48, 95% CI: 0.99-2.20, P=0.052), and there is no significant relationship between advanced maternal age and low birth weight (OR: 1.08, 95%
CI: 0.67-1.74, P=0.736).
Conclusion: Advanced maternal age is associated with higher risk of unintended pregnancy, preterm birth and cesarean
section but our findings did not support advanced maternal age as a risk factor associated with low birth weight.