Aging mothers, failing placentas? Association between maternal age and placental perfusion in a low-resource setting

The prevalence of pregnancies among women of advanced maternal age (AMA, ≥ 35 years) is increasing globally. Age-related vascular changes may influence placental perfusion, but evidence isolating maternal age from major confounders remains limited, particularly in low-resource settings. The objective of the study was to examine the association between maternal age and placental vascular resistance, measured using the umbilical artery pulsatility index (UA-PI). This prospective cross-sectional comparative study was conducted at a tertiary military hospital in Lagos, Nigeria. One hundred pregnancies at term were stratified into younger maternal age (<35 years, n = 50) and AMA (≥35 years, n = 50) groups. Umbilical artery Doppler assessments were performed at 37 weeks' gestation. Mean UA-PI values were compared across maternal age groups using one-way analysis of variance with Tukey post hoc testing. Effect sizes are presented with 95% confidence intervals. At 37 weeks' gestation, mean UA-PI was higher among women with AMA compared with younger women (0.98 ± 0.20 vs 0.80 ± 0.19; mean difference 0.18, 95% CI 0.08-0.28; p = 0.001). A progressive increase in UA-PI was observed across age categories (<25, 25-34, 35-40, ≥ 41 years; p = 0.006). Advanced maternal age was associated with higher umbilical artery vascular resistance in this cohort. These findings support further evaluation of Doppler-based placental surveillance strategies for AMA pregnancies, particularly in low-resource settings.