Empirical Analysis of the Relationship Between Antenatal Care Quality and Perinatal Outcomes Across Six Geopolitical Zones in Nigeria

Antenatal care quality, rather than mere attendance, is increasingly recognised as the critical determinant of its protective effect on maternal and perinatal outcomes, yet a multi-zone empirical analysis of this relationship is absent from the Nigerian literature. This study empirically analyses the association between antenatal care quality indicators and perinatal outcomes across six geopolitical zones in Nigeria. A multi-site cross-sectional study enrolled 600 women who delivered within the preceding four weeks, recruiting 100 per zone from public hospitals in Lagos, Enugu, Port Harcourt, Abuja, Kano, and Maiduguri. Antenatal care quality was assessed using a validated composite index measuring iron supplementation, tetanus toxoid receipt, blood pressure monitoring, malaria prophylaxis, and birth preparedness counselling completeness. Perinatal outcomes included gestational age at delivery, birth weight, and seven-day neonatal survival. Multivariate regression analysis controlling for sociodemographic confounders shows that high-quality antenatal care index scores were independently associated with significantly reduced low birth weight (adjusted OR 0.41) and preterm delivery (adjusted OR 0.49). Zone-level variation was substantial, with North West and North East zones showing the lowest quality index scores and correspondingly worst perinatal outcomes. The study provides empirical evidence that antenatal care content quality, not attendance quantity alone, drives perinatal benefit. Recommendations target national antenatal care quality audit systems and zone-specific content strengthening. Keywords: antenatal care quality, perinatal outcomes, multi-zone study, Nigeria, low birth weight