The effect of overweight and obesity on fecundity and pregnancy outcome amongst women in sub-Saharan Africa

Background: Obesity is an emerging public health concern in Sub-Saharan Africa and adult women are the population group most likely to be obese. Previous research conducted in high-income countries has demonstrated that high body mass index (BMI) has an adverse effect on a large number of reproductive outcomes; however no study has investigated this in Sub-Saharan Africa. Methods: Cross-sectional data of women (15-49 years) from twenty-seven countries in Sub- Saharan Africa, collected through the Demographic and Health Surveys, were used to examine the effect of BMI on female fecundity and adverse pregnancy outcomes. Underweight women (BMI <18.5kg/m2) were excluded. Multivariable regression models were used to examine four outcomes: (i) subfertility; (ii) time to first conception; (iii) caesarean delivery; (iv) neonatal death. The fecundity results were supplemented with a systematic review on the effect of BMI on waiting time to conception. Results: Increased BMI was associated with significantly increased odds of subfertility (Obese OR: 1.51; 95% Cl: 1.35-1.69). Five years after first marriage, 17% of non-contracepting obese (BMI Z30kg/m2) and 12.5% of pre-obese women (BMI 25-29.9kg/r2) had yet to conceive compared to 9.3% of optimal women (BMI 18.5-24.9kg/r2); however this difference was not statistically significant (p=0.5378). Each unit increase in maternal BMI (kg/m2)w as significantly associated with a 7% increase in the odds of caesarean delivery (OR:1 .07;9 5%C l: 1.06-1.08).M maternal obesity as significantly associated with increased odds of neonatal death (OR:1 .52;9 5%C I:1 .18-1.97). The association was strongest or deaths occurring in the first week of life to infants delivered Vaginally (OR: 2.43; 95% Cl: 1.43-3.88). Conclusions and Implications: Increased BMI is associated with adverse reproductive outcomes in the Sub-Saharan context. The risk is particularly strong or outcomes occurring around the intrapartum period. Overweight/obesity should be recognised as a risk actor for adverse reproductive outcomes i n Sub-Saharan Africa.