Risk Factors for Adverse Maternal and Neonatal Outcomes Within Two Hours After Delivery: A National Registry-Based Multinomial Logistic Regression Study in Iran

Abstract

Background: Perinatal health indicators, such as early neonatal mortality within 2 hours after birth, stillbirth, maternal mortality, and obstetric complications, are important public health concerns. Identifying associated maternal and fetal factors may inform clinical risk assessment and healthcare planning. Objectives: This study examined associations between maternal and fetal characteristics and adverse perinatal outcomes using data from the Iranian national birth registry. Methods: This retrospective, registry-based study used a complete national extraction of 1,431,597 mother–neonate records from Iran in 2017. Maternal and neonatal variables included maternal age (< 18, 18 - 35, and > 35 years), neonatal sex, hypertensive disorders, a history of neonatal death, previous stillbirth, premature rupture of membranes (PROM), non-gestational diabetes mellitus, placenta accreta, and fetal arrhythmias. Multivariable multinomial logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs). Statistical significance was defined as P < 0.05. Results: Extremes of maternal age, hypertensive disorders, a history of adverse obstetric outcomes, PROM, non-gestational diabetes mellitus, placenta accreta, fetal arrhythmias, and male sex were associated with increased odds of adverse neonatal and maternal outcomes, including stillbirth, early neonatal mortality (≤ 2 h), and admission to the intensive care unit (ICU). Conclusions: The observed associations may help identify high-risk pregnancies; however, the observational design does not support causal inference. Further prospective studies are required.