Associations of maternal prepregnancy body mass index and gestational weight gain with cardio‐metabolic risk factors in adolescent offspring: a prospective cohort study

OBJECTIVE: To assess the associations of maternal prepregnancy body mass index (BMI) and rates of early-pregnancy, mid-pregnancy and total gestational weight gain with adolescent body fat distribution and cardio-metabolic outcomes. DESIGN: Population-based prospective cohort study. SETTING: Western Australia. POPULATION: Thousand three hundred and ninety-two mothers and their children. METHODS: Maternal prepregnancy weight was assessed by questionnaire. Maternal weights at a mean of 16.5 ± 2.2 SD and 34.1 ± 1.5 SD weeks of gestation were obtained from medical records. Offspring adiposity and cardio-metabolic outcomes were assessed at a median age 17.0 years [95% confidence interval (CI) range: 16.7, 17.7]. MAIN OUTCOME MEASURES: Adolescent BMI, waist circumference (WC), waist-to-hip ratio (WHR), blood pressure, total and HDL-cholesterol, triglycerides, insulin, glucose and HOMA-IR. RESULTS: Higher prepregnancy BMI was associated with higher adolescent BMI, WC, WHR, systolic blood pressure, insulin, glucose and HOMA-IR levels (P-values <0.05). Adjustment for adolescent current BMI attenuated the associations of prepregnancy BMI with adolescent cardio-metabolic outcomes. Higher weight gain in early-pregnancy, but not mid-pregnancy, was associated with higher adolescent BMI, WC and WHR (P-values <0.05), but not with other cardio-metabolic risk factors. Total gestational weight gain was associated with adolescent BMI and WC (P-values <0.05). Higher prepregnancy BMI and early-pregnancy weight gain were associated with increased risks of the high-metabolic risk cluster in adolescents (OR 1.57, 95% CI 1.33, 1.85 and OR 1.23, 95% CI 1.03, 1.47 per SD increase in prepregnancy BMI and early-pregnancy weight gain, respectively). CONCLUSIONS: Higher maternal prepregnancy BMI and early-pregnancy weight gain rate are associated with an adverse adolescent cardio-metabolic profile. These associations are largely mediated by adolescent BMI.