Relationship between maternal pre-pregnancy body mass index, gestational weight gain and childhood fatness at 6-7 years by air displacement plethysmography

This study aims to investigate the effect of maternal pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) on offspring body composition. In this prospective cohort study, offspring body composition at 6 years of age was obtained through air displacement plethysmography. Linear regression was used to obtain crude and adjusted coefficients. Information regarding offspring body composition and maternal pre-pregnancy BMI was available for 3156 children and on offspring body composition and GWG for 3129 children. There was a direct association of maternal pre-pregnancy BMI and GWG with offspring's fat mass (FM), fat-free mass (FFM), fat mass index (FMI), fat-free mass index (FFMI) and body fat percent (BF%) in crude and adjusted analyses. After adjustment for co-variables, for each kgm(-2) of maternal pre-pregnancy BMI increase, there was a mean increment of 0.13kg in the offspring FFM, 0.06kgm(-2) in FFMI, 0.11kg in FM, 0.07kgm(-2) in FMI and 0.18% in BF%. For each kilogram of maternal GWG increase, there was a mean increment of 0.08kg in offspring's FM, 0.05kgm(-2) in FMI, 0.04kg in FFM, 0.01kgm(-2) in FFMI and 0.18 % in BF%. Mothers with a higher pre-pregnancy BMI or GWG tend to have children with greater adiposity at age 6 years. Fetal overnutrition is more likely among mothers with greater BMI during pregnancy; as a consequence, it can accelerate the childhood obesity epidemic.