The Prevalence of Maternal Obesity at First Antenatal Visit and Pregnancy Outcomes: A Prospective Cohort Study in a Southern Nigerian Region

Abstract

Background: Alarmingly, high prevalence of obesity has been reported globally. There is a paucity of data on maternal obesity and pregnancy outcome, especially in sub-Saharan Africa. Aim: The aim of this study was to determine the prevalence of obesity among pregnant women at their first antenatal visit and its impact on pregnancy outcome. Patients, Materials and Methods: This was an institution-based prospective cohort study involving 1050 pregnant women. Their baseline body mass index (BMI) was calculated and obesity was diagnosed based on the World Health Organisation cutoff of 30 kg/m2. They were followed up to delivery and major maternal and perinatal outcomes were compared between the obese and nonobese women using appropriate statistical models. Results: The prevalence of obesity at the first ANC visit among the women was 29.55%. Obese pregnant women had higher risk for hypertensive disorders (P = 0.049, relative risk [RR] =1.40; 95% [CI]: 1.02–1.92) and gestational diabetes, gestational diabetes mellitus (GDM), (P = 0.003, RR = 2.3; 95% CI: 1.59–3.35). Other maternal outcomes were comparable in both groups. Obese women also had higher risk of giving birth to a macrosomic infant (P = 0.001, RR = 2.65; 95% CI: 2.23–3.15). Baseline BMI had stronger positive correlation with infant birth weight than gestational weight gain (r = 0.43 vs. r = 0.18), respectively. Conclusion: The prevalence of obesity in pregnancy in this region is high and carries higher risk for major pregnancy complications such as preeclampsia and GDM as well as giving birth to a macrosomic infant. Prepregnant lifestyle modification is, therefore, advised for such women.

Keywords

• birth weight
• foetal macrosomia
• gestational diabetes
• gestational weight gain
• hypertensive disorder
• obesity