Patterns of gestational weight gain and its association with birthweight in Nigeria

Background: Despite the increasing global importance of gestational weight gain (GWG) and its impact on birthweight, little is known about the patterns of GWG in African populations.Objectives: To determine the pattern of GWG and its association with birthweight in Nigeria.Methods: It was a longitudinal study of 200 pregnant women receiving antenatal care at two tertiary hospitals in Enugu, south eastern Nigeria. The women were consecutively recruited at <14 weeks gestation and their body mass indexes recorded upon recruitment. Thereafter, weight measurements were taken at each visit until 38–39 weeks.Results: Mean total GWG was 10.7 ± 3.4 kg, while mean birthweight was 3.3 ± 0.6 kg. GWG in second trimester had positive correlation with birthweight (r = 0.164, P = 0.02). Obese women gained above the recommended limits by the "institute of medicine" while underweight women gained below the limits. Excessive total GWG was associated with higher risk of macrosomia [8/21 (38.1%) vs. 7/179; RR: 9.74; 95% CI: 3.9–24.2; P < 0.001] while inadequate total GWG was associated with higher risk of low birth weight [7/72 (9.7%) vs. 3/128 (2.3%; RR: 4.15; 95% CI: 1.1–15.4; P = 0.03]. Maternal age of <35 years, high social class, nulliparity, and regular antenatal care were associated with normal GWG while maternal age <35 years and regular antenatal care were associated with normal birthweight (P < 0.05).Conclusions: Women should be counseled on the factors that influence GWG and birthweight. Interventions to assist women achieve appropriate GWG may need to include components related to improved dietary intake for the underweight and increased physical activity for the obese.Keywords: birthweight, body mass index, pregnancy, Nigeria, weight gai