Maternal weight gain in different periods of pregnancy and childhood cardio-metabolic outcomes. The Generation R Study.

BACKGROUND: Excessive gestational weight gain seems to be associated with offspring cardio-metabolic risk factors. Little is known about the critical periods of gestational weight gain. We examined the associations of maternal weight gain in different periods of pregnancy with childhood cardio-metabolic risk factors.

METHODS: In a population-based prospective cohort study from early pregnancy onwards among 5908 mothers and their children, we obtained maternal prepregnancy weight and weight in early, mid and late pregnancy. At the age of 6 years (median: 72.6 months; 95% range: 67.9, 95.8), we measured childhood body mass index (BMI), total body and abdominal fat distribution, blood pressure and blood levels of lipids, insulin and c-peptide.

RESULTS: Overall, the associations of maternal prepregnancy weight with childhood outcomes were stronger than the associations of maternal gestational weight gain. Independent from maternal prepregnancy weight and weight gain in other periods, higher weight gain in early pregnancy was associated with higher childhood BMI, total fat mass, android/gynoid fat mass ratio, abdominal subcutaneous fat mass and systolic blood pressure (P-values<0.05). Independent associations of maternal weight gain in early pregnancy with childhood abdominal preperitoneal fat mass, insulin and c-peptide were of borderline significance. Higher weight gain in mid pregnancy was independently associated with higher childhood BMI, total and abdominal subcutaneous fat mass and systolic blood pressure (P-values<0.05). The associations for childhood cardio-metabolic outcomes attenuated after adjustment for childhood BMI. Weight gain in late pregnancy was not associated with childhood outcomes. Higher weight gain in early, but not in mid or late pregnancy, was associated with increased risks of childhood overweight and clustering of cardio-metabolic risk factors (odds ratio (OR) 1.19 (95% confidence interval (CI): 1.10, 1.29) and OR 1.20 (95% CI: 1.07, 1.35) per standard deviation increase in early gestational weight gain, respectively).

CONCLUSIONS: Higher weight gain in early pregnancy is associated with an adverse cardio-metabolic profile in offspring. This association is largely mediated by childhood adiposity.