Abstract
BACKGROUND: Low birth weight (LBW), defined as birth weight less than 2500 g regardless of gestational age, remains a pressing global health issue. It significantly contributes to neonatal mortality (60-80% of deaths), developmental delays and increased risk of chronic diseases in adulthood. Despite interventions, LBW remains prevalent in Ethiopia. This study aimed to identify the key risk factors for LBW in public hospitals in Addis Ababa, with a focus on maternal nutrition and prenatal care two underexplored but modifiable determinants: maternal nutrition and prenatal care. METHODS: A cross-sectional study was conducted in 2024 using data from 722 mothers selected via simple random sampling across four public hospitals in Addis Ababa. Birth weight was categorised into low and not low groups. To account for hospital-level variability, a multilevel binary logistic regression model was employed, treating hospitals as random effects, to identify maternal, nutritional and prenatal care factors associated with LBW. RESULTS: The prevalence of LBW was 12%. The multilevel binary logistic regression model revealed significant between-hospital variability in LBW outcomes (variance=0.25; 95% CI: 0.12 to 0.55). Increased odds of LBW were associated with maternal age>34 years (adjusted OR (AOR)=2.51; 95% CI: 1.20 to 5.50), unplanned pregnancy (AOR=1.60; 95% CI: 1.42 to 1.92), family size >4 (AOR=2.15; 95% CI: 1.35 to 3.45), alcohol use during pregnancy (AOR=1.62; 95% CI: 1.28 to 2.01), delayed antenatal care initiation in the third trimester (AOR=1.14; 95% CI: 1.02 to 1.62) and heavy maternal workload (AOR=1.12; 95% CI: 1.01 to 1.64). Protective factors included regular antenatal care follow-up (AOR=0.29; 95% CI: 0.12 to 0.64), eating extra meals during pregnancy (AOR=0.46; 95% CI: 0.22 to 0.87), interpregnancy interval>24 months (AOR=0.55; 95% CI: 0.29 to 0.69), maternal height≥155 cm (AOR=0.49; 95% CI: 0.22 to 0.87) and pre-pregnancy weight≥50 kg (AOR=0.20; 95% CI: 0.06 to 0.46). CONCLUSIONS: This study underscores that maternal age, pregnancy planning, family size, antenatal care access and timing, workload, alcohol use and nutritional practices are associated with LBW. The observed variation across hospitals suggests institutional differences may also influence outcomes. Strengthening maternal health programmes and improving hospital-level care could reduce LBW prevalence in Addis Ababa.