Advanced Maternal Age Pregnancies: Perinatal Outcomes and Maternal Characteristics in Comparison with Women Aged 20–35 Years

INTRODUCTION: Advanced maternal age (AMA) pregnancies are associated with increased maternal and perinatal risks; however, the relative contribution of maternal age itself versus accompanying maternal characteristics remains debated. This study aimed to evaluate maternal characteristics and perinatal outcomes in women aged ≥35 years compared with those aged 20–35 years.
METHODS: This retrospective comparative cohort study included singleton pregnancies delivered between January 2022 and July 2025 at a tertiary referral center. Women aged ≥35 years constituted the AMA group, while women aged 20–35 years served as controls. Maternal characteristics, obstetric complications, mode of delivery, and perinatal outcomes were compared between groups. Neonatal intensive care unit (NICU) admission was defined as the primary outcome.
RESULTS: A total of 599 women were included (300 AMA, 299 controls). Overweight/obesity, gestational diabetes mellitus, chronic hypertension, and cesarean delivery were significantly more frequent in the AMA group (all p < 0.01). NICU admission was higher among infants born to women aged ≥35 years compared with controls (25.0% vs. 10.4%, p < 0.001). Other key neonatal outcomes, including birth weight, Apgar scores, fetal growth restriction, and preterm birth, did not differ significantly between groups. Multivariable logistic regression analysis demonstrated that increased body mass index, gestational diabetes mellitus, and cesarean delivery were independently associated with the advanced maternal age group.
DISCUSSION AND CONCLUSION: Advanced maternal age was associated with a higher burden of maternal comorbidities and increased cesarean delivery rates, whereas most neonatal outcomes were comparable between age groups. These findings suggest that adverse perinatal outcomes in AMA pregnancies are largely driven by coexisting maternal characteristics rather than maternal age alone when appropriate care is provided.

Keywords: Advanced maternal age, Perinatal outcomes, Neonatal intensive care unit, Cesarean delivery, Gestational diabetes mellitus