The Impact of Advanced Maternal Age on Pregnancy Complications and Neonatal Outcomes.

: This study aimed to evaluate and compare maternal and fetal outcomes between pregnancies in women aged 40 and over and those in women under 40 years of age at a tertiary care hospital. : A retrospective cohort study was conducted at Necmettin Erbakan University Medical Faculty Hospital, analyzing data from 345 women aged 40 and over and 366 women under 40 who delivered between January 2015 and December 2024. Maternal and perinatal outcomes-including mode of delivery, gestational age, birth weight, and complications such as gestational diabetes, preeclampsia, and postpartum hemorrhage-were compared between the two groups. : Women aged 40 and over had significantly higher rates of cesarean section (73% vs. 36.1%, < 0.0001), preterm delivery (27.8% vs. 18%, = 0.002), and gestational diabetes (14.8% vs. 7.7%, = 0.002). Additionally, these women had a higher incidence of preeclampsia (13% vs. 5.7%, = 0.001) and postpartum hemorrhage (18% vs. 10.5%, = 0.003). Despite these increased risks, the 5 min APGAR score was significantly higher in the ≥40 age group (median 8 vs. 7, < 0.0001). The incidence of chromosomal abnormalities was significantly higher in patients≥ 40 years, with 5 cases (1.4%) reported, compared to no cases (0%) in the <40 age group ( = 0.025). : This study shows that pregnancies in women aged 40 and above carry higher maternal and fetal risks compared to younger women. Complications such as preterm labor, cesarean delivery, gestational diabetes, and preeclampsia occur more frequently in this group. However, with careful prenatal care, positive neonatal outcomes are often achievable, highlighting the need for age-specific management and early risk detection.