From pregnancy to breastfeeding: adequate maternal body mass index is essential to prevent a high body mass index in your children.

OBJECTIVES: To verify the associations between prenatal and perinatal factors with offspring body mass index (BMI) and the moderator role of maternal BMI in this relationship. METHODS: Cross-sectional study developed with 1,562 children and adolescents aged between 6 and 17 years, as well as their mothers, from southern Brazil. The prenatal and perinatal factors, weight, and height for the calculation of maternal BMI were self-reported. For the calculation of BMI, weight and height of the child/adolescent were measured on an anthropometric scale with a coupled stadiometer. Linear regression models were used for the moderation analysis. All analyzes were adjusted for the mother's and child's age, sex, sexual maturation, skin color/race, and educational level. RESULTS: cesarean as type of delivery (ß=0.66; 95% CI=0.22 1.04; p=0.002) and pregnancy complications (ß=0.60; 95% CI=0.15 1.04; p=0.002) were positively associated with offspring BMI. Schoolchildren who were breastfed for 4-6 months showed -0.56 kg/m2 of BMI (95% CI=-1.06-0.06; p=0.02). Birth weight was also associated with BMI, with low weight being inversely (ß=-0.59; 95% CI=-1.03-0.15; p=0.008), while overweight was positively related (ß=0.84; 95% CI=0.08 1.60; p=0.02). The moderation analysis indicated a positive interaction between the mother's BMI and cesarean, pregnancy complications, and smoking with the offspring's BMI. On the other hand, there was an inverse association between breastfeeding from 7 to 12 months and the offspring BMI, only in mothers with high BMI. CONCLUSIONS: Adequate maternal BMI is essential to prevent a high BMI in their children, especially when considering the influence of prenatal and perinatal risk factors.

Relationship between rs9939609 FTO polymorphism with waist circumference and body fat is moderated by ponderal index at birth in youth.

OBJECTIVE: The goal of this study was to analyze whether the relationship between the rs9939609 polymorphism of the fat mass and obesity-associated gene (FTO) with nutritional status is moderated by the ponderal index (PI) at birth in children and adolescents. METHODS: A cross-sectional study evaluated 382 schoolchildren aged 6-17 years. Anthropometric variables such as waist circumference (WC), body mass index (BMI) and body fat percentage (BF%) were used to assess nutritional status. Weight and height at birth were used for the PI calculation, which was divided into tertiles (lower, middle and upper). To compare the continuous variables between genotypes of the rs9939609 polymorphism, a recessive model (TT/AT vs. AA) and covariance analysis (ANCOVA) were used. RESULTS: The AA genotype of the rs9939609 polymorphism was associated with higher WC in schoolchildren born with lower PI (ß = 4.40; p = .048). However, for BF%, the genotype association was found in the upper PI tertile (ß = 7.35; p = .040). CONCLUSION: The relationship between WC and BF% with rs9939609 polymorphism (FTO) seems to be moderated by PI at birth. This is an important insight, since the data for intrauterine growth, genetic factors and the presence of obesity in children and adolescents are still contradictory.