Maternal body mass index, gestational weight gain, and childhood abdominal, pericardial, and liver fat assessed by magnetic resonance imaging

Background/Objectives Maternal obesity and excessive gestational weight gain are associated with an increased risk of obesity in offspring. It remains unclear whether maternal adiposity also affects organ fat, which has important adverse cardiometabolic health consequences and whether the associations reflect intrauterine causal mechanisms. We examined the associations of parental pre-pregnancy body mass index (BMI) and gestational weight gain with general, abdominal, pericardial, and liver fat in 10-year-old children. Subjects/Methods In a population-based prospective cohort study among 2354 parents and their children, we obtained prepregnancy maternal and paternal BMI and gestational weight gain and offspring BMI, fat mass index (total fat/height(4)) by dual-energy X-ray absorptiometry, and subcutaneous fat index (subcutaneous fat/height(4)), visceral fat index (visceral fat/height(3)), pericardial fat index (pericardial fat/height(3)), and liver fat fraction by magnetic resonance imaging (MRI) at 10 years. Results A 1-standard deviation score (SDS) higher maternal pre-pregnancy BMI was associated with higher childhood BMI (difference 0.32 (95% confidence interval (CI) 0.28, 0.36) SDS), fat mass index (difference 0.28 (95% CI 0.24, 0.31) SDS), subcutaneous fat index (difference 0.26 (95% CI 0.22, 0.30) SDS), visceral fat index (difference 0.24 (95% CI 0.20, 0.28) SDS), pericardial fat index (difference 0.12 (95% CI 0.08, 0.16) SDS), and liver fat fraction (difference 0.15 (95% CI 0.11, 0.19) SDS). After conditioning each MRI adiposity measure on BMI at 10 years, higher maternal pre-pregnancy BMI remained associated with higher childhood subcutaneous and visceral fat indices. Smaller but not statistically different effect estimates were observed for paternal BMI. Gestational weight gain was not consistently associated with organ fat. Conclusions Higher maternal pre-pregnancy BMI, but not gestational weight gain, was associated with higher general and organ fat. Similar associations of pre-pregnancy maternal and paternal BMI with offspring adiposity suggest a role of family shared lifestyle factors and genetics.