RESUMO
INTRODUCTION: low birth weight (LBW) remains a devastating adverse pregnancy outcome in low and middle income countries (LMICs). There is evidence showing that maternal demographic and pregnancy-related characteristics are associated with LBW. Little attention is given to paternal characteristics, which may be associated with a higher risk of LBW. This study aimed to assess the effect of paternal characteristics on LBW among singleton deliveries at Kilimanjaro Christian Medical Centre (KCMC) zonal referral hospital in Kilimanjaro region, northern Tanzania. METHODS: this was a secondary analysis of a hospital-based cohort study from maternally-linked medical birth registry data at KCMC between 2000 and 2018. A total of 47,035 singleton deliveries were included in this study. Data analysis was performed using statistical package for social sciences (SPSS), version 20 (IBM Corp., Armonk, NY). Relative risk and corresponding 95% confidence intervals (CI) were used to determine association between LBW and paternal characteristics using log-binomial regression models, with robust standard errors to account for clustering of deliveries within mothers. RESULTS: the proportion of LBW during the study period was 9.6%. After adjusting for maternal characteristics, higher risk of LBW was among fathers with low education level (RR=1.72, 95% CI: 1.22, 2.41, p=0.002), aged ≤24 years old (RR=1.37, 95% CI: 1.21, 1.55), and those unemployed (RR= 1.11, 95% CI: 1.01, 1.21). Lower risk of LBW was among fathers aged ≥40 years (RR=0.97, 95% CI: 0.88, 1.08), but this association was not statistically significant. CONCLUSION: the study confirmed paternal young age (≤24 years old), paternal low education level and unemployment as predictors for LBW. Current evidence on the effect of paternal characteristics on LBW might suggest that programs and policies should target their engagement as a key strategy for improving birth outcomes during the perinatal period. Future studies should assess how paternal factors are associated with the risk of adverse birth outcomes.