Prevalence and factors associated with underweight among 15–49-year-old women in Sierra Leone: a secondary data analysis of Sierra Leone demographic health survey of 2019

Background Women are at higher risks of being underweight than men due to biological, socio-economic, and cultural factors. Underweight women have high risks of poor obstetric outcomes. We aimed to determine the prevalence and factors associated with being underweight among women of reproductive age (15–49 years) in Sierra Leone. Methods We used Sierra Leone Demographic and Health Survey (2019-SLDHS) data of 7,514 women aged 15 to 49 years, excluding pregnant, post-natal, lactating, and post-menopausal women. A multistage stratified sampling approach was used to select study participants, and data was collected using validated questionnaires. A multivariable logistic regression analysis was used to determine factors associated with underweight among 15–49-year-old women in Sierra Leone. Ethical approval for the study was obtained. Results The prevalence of underweight was 6.7% (502/7,514). Underweight was likely among age-group of 15–24 years, AOR = 2.50,95%CI:2.39–2.60; p < 0.001 compared to 25–34 year age-group and likely among women with parity of one to four, AOR = 1.48,95%CI:1.08–2.03; p = 0.015 compared to women who never gave birth. Underweight was unlikely among women who did not listen to radios AOR = 0.67,95%CI:0.55–0.83; p < 0.001 compared to those who did; women from the north AOR = 0.73,95%CI:0.56–0.96; p = 0.026 compared to the east, and not married women AOR = 0.59,95%CI:0.47–0.76; p < 0.001 compared to married. All household wealth indices were not significantly associated with underweight. Conclusion The prevalence of underweight among women in the reproductive age (15–49 years) in Sierra Leone was 6.7% and it is lower compared to global and most sub-Saharan African data. Factors associated with underweight were 15–24-year age-group, and parity of one to four. Being underweight was unlikely among women who did not listen to radios, women from the north and not married. All household wealth indices were not significantly associated with underweight. Even though household wealth indices were not significantly associated with being underweight, most underweight women 68.7% (345/502) were in the poorest, poorer, and middle household wealth indices. The need to address socio-economic determinants of underweight among women (aged 15–49 years) due to household poverty is a priority in Sierra Leone.