Associations of body mass index and gestational weight gain with term pregnancy outcomes in urban Cameroon: a retrospective cohort study in a tertiary hospital

Abstract

Background: Obesity is a rising public health issue worldwide. Guidelines regarding maternal body mass index (BMI) and gestational weight gain (GWG) are missing in Cameroon where maternal mortality rate remains very high. We hypothesized that obesity and inappropriate GWG are associated with poor pregnancy outcomes. We aimed at assessing associations of BMI and GWG with pregnancy outcomes. Methods: This was a retrospective cohort study at the Yaoundé Central Hospital. We included women with term singleton deliveries in the post-partum ward. The World Health Organisation classification of BMI and the United States Institute Of Medicine (IOM) categories of GWG were used to stratify participants. Poor maternal outcome was defined by the occurence of caesarean section, preeclampsia or obstetrical haemorrhage. Poor perinatal outcome was defined by the occurence of perinatal death, admission in intensive care unit, low birth weight, macrosomia or fifth minute Apgar score <7. Multiple logistic regressions were used to calculate unadjusted and adjusted Odds Ratios (uOR, aOR) for poor maternal outcome (PMO) and for poor perinatal outcome (PPO) in each category of BMI and GWG. Adjustment was done for age, scarred uterus, sickle cell disease, malaria, human immunodeficiency virus (HIV) infection, parity and smoking. Results: Of the 462 participants, 17 (4 %) were underweight (BMI < 18.5), 228 (49 %) had normal pre-pregnancy BMI, 152 (33 %) were overweight (25 ≤ BMI < 30) and 65 (14 %) were obese (BMI ≥ 30). Following the IOM recommendations, GWG was normal for 186 (40 %) participants, less than recommended for 131 (28 %) and above the recommended norms for 145 (32 %). GWG above the IOM recommendation was significantly associated with PMO (aOR: 1.7, 95 % CI 1.1-2.8). GWG less than the IOM recommended values, overweight and obesity were not significantly associated with poor pregnancy outcomes. Conclusion: While waiting for local recommendations for GWG, the IOM recommendations can be used for Cameroonian women as far as maternal outcome is concerned. Unlike in studies in different ethnic and racial groups, abnormal BMI was not associated with poor pregnancy outcomes in our cohort of Cameroonian women.