Associations of gestational weight gain with short- and longer-term maternal and child health outcomes

Abstract

The authors investigated the rate of gestational weight gain associated with the lowest combined risk of 5 short- and longer-term maternal and child health outcomes for 2,012 mother-child pairs recruited in 1999-2002 into Project Viva, a prebirth cohort study in Massachusetts. Within each maternal prepregnancy body mass index (BMI, kg/m(2)) stratum, they performed a logistic regression analysis predicting all 5 outcomes, from which they determined the rate of gain at which average predicted prevalence of the adverse outcomes was the lowest. The mean rate of total gestational weight gain was 0.39 kg/week (standard deviation, 0.14). The prevalence of small for gestational age was 6%, large for gestational age was 14%, preterm delivery was 7%, substantial postpartum weight retention was 16%, and child obesity was 10%. The lowest predicted outcome prevalence occurred with a 0.28-kg/week gain for women whose BMI was 18.5-24.9, a 0.03-kg/week loss for a BMI of 25.0-29.9, and a 0.19-kg/week loss for a BMI of >or=30.0 kg/m(2)--the lowest observed weight changes in overweight and obese women. For normal-weight and overweight women, lowest-risk gains varied modestly with adjustment for maternal characteristics and with different outcome weightings. For obese women, the lowest-risk weight change was weight loss in all models. Recommendations for gestational weight gain for obese women should be revised.

Figure 1.

Predicted probabilities of small-for-gestational-age birth, large-for-gestational-age birth, preterm delivery, maternal substantial postpartum weight retention, and child obesity according to rate of gestational weight gain during pregnancy among women with a body mass index of A) 18.5–24.9 kg/m² (“normal weight”), B) 25.0–29.9 kg/m² (“overweight”), and C) ≥30.0 kg/m² (“obese”): results from 2,012 Massachusetts mother-child pairs enrolled in Project Viva, 1999–2002.

Figure 2.

Average predicted probability of 5 adverse outcomes (small-for-gestational-age birth, large-for-gestational-age birth, preterm delivery, maternal substantial postpartum weight retention, and child obesity) according to maternal prepregnancy body mass index and rate of gestational weight gain during pregnancy: results from 2,012 Massachusetts mother-child pairs enrolled in Project Viva, 1999–2002. Body mass index was categorized as 18.5–24.9 kg/m² (“normal weight”), 25.0–29.9 kg/m² (“overweight”), and ≥30.0 kg/m² (“obese”). Arrows indicate the nadir of each curve.