Overweight and Obesity among Women with Pregnancy-induced Hypertension in Sierra Leone: Age Patterns and Comparison with the National Population of Women of Reproductive Age

Background: Overweight and obesity may contribute to hypertensive disorders of pregnancy, but age-specific patterns among affected women outside Sierra Leone’s capital remain insufficiently described. This study examined body mass index (BMI) among women with pregnancy-induced hypertension (PIH) and compared overweight or obesity prevalence with national estimates. Methods: A retrospective review included 553 women with recorded PIH at Bo Government Hospital from January 2018 to June 2023. BMI categories were examined by age using permutation χ² and Cochran–Armitage tests. Comparisons used age-specific estimates for 7,514 non-pregnant women in the 2019 Sierra Leone Demographic and Health Survey. Prevalence ratios, indirect standardisation and a tipping-point bias analysis were used to examine differences and possible misclassification arising from gestational weight gain. Results: Among women with PIH, 37.1% were overweight, 20.4% were obese and 1.8% were underweight. The combined prevalence of overweight or obesity was 57.5% (95% confidence interval [CI] 53.3–61.6), without a significant age trend (p = 0.49). Prevalence was 60.8% among those aged 16–20 years. Age-specific prevalence ratios relative to the national reference were 3.50, 1.77 and 1.62 from youngest to oldest. The age-standardised prevalence ratio was 2.43 (95% CI 2.17–2.71). The modelled excess disappeared when 58.8% of women classified as overweight or obese were assumed to have been misclassified. Conclusions: Overweight and obesity were more prevalent among women with PIH than among non-pregnant women nationally, particularly at younger ages. The comparison should be interpreted cautiously because BMI was recorded during pregnancy.