Gestational weight gain and associated factors in a tertiary hospital in Southwest Nigeria: A cohort study

Abstract

Background: Gestational weight gain (GWG) is an important determinant of maternal and foetal wellbeing. Evidence
suggests that there is heterogeneity in GWG across countries and regions based on the influence of several factors. This study
was designed to investigate GWG, associated factors, and pregnancy outcome among women who gave birth at Babcock
University Teaching Hospital, Nigeria.
Methodology: A prospective cohort study carried out on 220 pregnant women who registered for antenatal care before
gestational age of 13 weeks and recruited between June 2022 and May 2024. GWG was categorized into adequate, inadequate
or excessive according to the United States Institute of Medicine (IOM) guidelines. Logistic regression analysis was used to
investigate predictors of GWG, while Relative Risk was reported for pregnancy outcomes.
Results: Adequate GWG, inadequate GWG and Excessive GWG were achieved by 29.1%, 40.5% and 30.5% of the women,
respectively. The median (95% CI) GWG in all study participants was 9.8 (8.8-10.3) Kg. Older maternal age [OR 2.5(1.3-5.0);
P=0.013], multiparity [OR 8.2(1.3-51.8); P=0.025] and middle/upper socioeconomic class [OR 14.6(2.1-99.2); P=0.006]
predicted increased likelihood of inadequate GWG while being overweight [OR 0.2(0.1-0.4); P<0.001] and obese [OR
0.06(0.02-0.20); P<0.001] were associated with reduced likelihood of inadequate GWG. None of the variables studied
predicted excessive GWG. In terms of pregnancy outcome, women with inadequate GWG had a 30% reduced risk of
caesarean delivery compared to those with adequate GWG [RR 0.7(0.6-0.9); P= 0.036]. The mean birth weight of babies born
to women with inadequate GWG was significantly lower than that of babies born to women with adequate GWG (T-test =
2.998; P=0.003).
Conclusion: A substantial proportion of study participants had suboptimal GWG (inadequate and excessive), with only a third
meeting the IOM recommendations. There is a need for targeted counselling for older, multiparous, and upper socioeconomic
class women on adequate GWG.