Objective: Emerging evidence suggests that exposures during fetal life affect adult metabolism. We assessed the relationship between recalled maternal pre-pregnancy body mass, gestational weight gain (GWG), and adiposity in the daughter.
Design: Retrospective cohort study among mother-nurse daughter dyads in the Nurses' Health Study II and the Nurses' Mothers' Cohort. Mothers of participants completed questionnaires regarding their nurse daughter in 2001.
Participants: 26,506 mother-nurse daughter dyads born between 1946 and 1964.
Main outcome measures: Body mass index (BMI) of the nurse daughter at age 18 and in 2001.
Results: At age 18, 561 (2.1%) daughters were obese (BMI>30), and in 2001, 5442 (22.0%) were obese. Adjusting for covariates, women whose mothers had a recalled pre-pregnancy BMI of 29 had a 6.1-fold increased risk of obesity at age 18 and a 3.4-fold risk of obesity in 2001, compared with women whose mothers had a pre-pregnancy BMI of 21. We found a U-shaped association between recalled GWG and offspring obesity. Compared with a maternal weight gain of 15-19 lb, GWG <10 lb was associated with a significant increase in obesity risk at age 18 (odds ratio (OR) 1.54, 95% confidence interval (CI) 1.02-2.34) and in 2001 (OR 1.27, 95% CI 1.05-1.53). High weight gain (40+lb) was also associated with obesity risk at age 18 (OR 1.81, 95% CI 1.22-2.69) and in 2001 (OR 1.74, 95% CI 1.48-2.04). These associations were stronger among mothers who were overweight before pregnancy (P for interaction=0.03), and they persisted with adjustment for birth weight.
Conclusion: A high recalled pre-pregnancy BMI and extremes of recalled GWG are associated with an increased risk of adolescent and adult obesity in offspring, particularly when the mother is overweight. Pre-pregnancy weight and GWG may be modifiable fetal origins of overweight and obesity in women.