What is the influence of maternal weight gain in different gestational clinical conditions on the prole weight in pre‐school age?

The aim of the current study was to assess the influence of maternal weight gain in different clinical gestational conditions on the child's weight at pre-school age. This was a longitudinal observational study of a prospective and controlled multiple cohort of 372 mother-child pairs with four causal groups of different adverse intrauterine environments (smoking, diabetic, hypertensive and intrauterine growth-restricted pregnant women) and a control group, in the period of, from 2011 to 2016 in three hospitals in Porto Alegre (Brazil). Sociodemographic, prenatal and perinatal data were analysed. Gestational weight gain (GWG) was categorised as 'insufficient', 'adequate' and 'excessive'. The generalised estimation equations (GEE) model was used to assess changes in the z-score of the child's body mass index from birth to pre-school age according to the GWG and gestational group. The child's GWG and weight gain were adjusted for maternal age and education, marital status, family income, pregnancy planning, number of children, prepregnancy BMI, prenatal consultations and type of delivery. A triple interaction effect was observed involving the gestational group, weight gain and study time (p = 0.020) through an adjusted model. Maternal weight gain above the recommended is associated with a significant increase in the child's z - BMI score over time, except for children from pregnant smokers. Children from diabetic mothers , hypertensive mothers and the control group who had a weight gain above that recommended during pregnancy changed their nutritional status from eutrophic to overweight, becoming obese in the DM and hypertension groups and overweight in control. Monitoring of the GWG, especially in the presence of hypertensive diseases and DM, should be effective to prevent children from developing overweight or obesity in pre-school age with an important impact on health conditions in the future.