Maternal determinants of birth weight in Northern Ghana

Objectives Weight at birth is usually considered as an indicator of the health status of a given society. As a result this study was designed to investigate the association between birth weight and maternal factors such as gestational weight gain, pre-pregnancy BMI and socio-economic status in Northern Ghana. Methods The study was a facility-based cross-sectional survey conducted in two districts in the Northern region of Ghana. These districts were purposively sampled to represent a mix of urban, peri-urban and rural population. The current study included 419 mother-infant pairs who delivered at term (37-42 weeks). Mother's height, pre-pregnancy weight and weight changes were generated from the antenatal records. Questionnaires were administered to establish socio-economic and demographic information of respondents. Maternal factors associated with birth weight were examined using multiple and univariate regressions. Results The mothers were generally well nourished before conception (Underweight 3.82%, Normal 57.76%, Overweight 25.06% and Obesity 13.37%) but approximately half of them could not gain adequate weight according to Institute of Medicine recommendations (Low weight gain 49.64%, Adequate weight gain 42.96% and Excessive weight gain 7.40%). Infants whose mothers had excess weight gain were 431g (95% CI 18-444) heavier compared to those whose mothers gained normal weight, while those whose mothers gained less were 479g (95% CI -682- (-276) lighter. Infants of mothers who were overweight and obese before conception were 246g (95% CI 87-405) and 595g (95% CI 375-815) respectively heavier than those of normal mothers, whereas those whose mothers were underweight were 305g (95% CI -565 -(-44) lighter. The mean birth weight observed was 2.98 ± 0.68 kg. Conclusion Our findings show that pre-pregnancy body mass index and weight gain during pregnancy influence birth weight. Therefore, emphasis should be placed on counseling and assisting pregnant women to stay within the recommended weight gain ranges.