Higher Maternal BMI During Early Pregnancy Increases Risk of Childhood Overweight and Obesity

Recent findings presented at the European Congress on Obesity highlight the significant impact of a woman's BMI in early pregnancy on her child's growth trajectory and weight status over the years. The study emphasizes that women entering pregnancy with overweight or obesity are more likely to have children who develop overweight or obesity, with risks increasing as the child's age advances.

The research analyzed data from the LIMIT trial, involving 2,121 pregnant women with an average age of 29.4 years and a median BMI of 31.1 during early pregnancy. Participants were divided into two groups: one received dietary and lifestyle interventions aimed at promoting healthy eating and increased physical activity, while the other received standard antenatal care.

Interestingly, the study found that the maternal BMI at the start of pregnancy directly influences the child's weight from birth up to age ten. Each increase of 5 kg/m² in maternal BMI was associated with a rise in the child's BMI by approximately 0.11 kg/m² at birth and up to 0.74 kg/m² by age ten. Notably, this association became more evident during early school age (3–5 years) and was most pronounced at 8–10 years.

Additionally, paternal BMI was also linked to the child's weight outcomes, especially at older ages. The findings suggest that children born to mothers with higher BMI are at a greater risk of developing overweight and obesity, independent of maternal lifestyle interventions during pregnancy.

Professor Jodie Dodd from the University of Adelaide explained that lifestyle improvements during pregnancy primarily reduce risks like high birth weight but do not significantly alter long-term growth patterns or obesity risk. Therefore, focusing on maternal health and weight before pregnancy is crucial. The study underscores the importance for healthcare providers to support women and their families in optimizing health prior to conception to help break the cycle of intergenerational obesity.