Does the Intrauterine Environment Influence Physical Activity During Childhood?

Background: Previous studies using animal models have shown that a compromised intrauterine environment influences locomotor behavior during postnatal life. However, there is limited research in humans examining this issue. In this study maternal body mass index (BMI) and birth weight (BW) were used as proxies of the fetal environment. PURPOSE: To determine if BW and maternal BMI were associated with physical activity in children. METHODS: Sixty-five children ranging from 3 to 8 years of age participated in this study. BW and maternal BMI were self reported. Habitual physical activity was determined by a MTI accelerometer. Partial correlation, controlling for age and gestational age, was used to identify relationships between birth weight, maternal BMI, BW x maternal BMI interactions and physical activity. RESULTS: Mean BW was 3.4 ± 0.5 kg and mean maternal BMI was 25.9±5.4 kg/m2. The total physical activity was 824±210 counts/min with a mean MVPA of 272.9 ± 62 min/day. Significant correlations were not identified between maternal BMI, BW, and physical activity parameters; however the general trend was in the expected direction (r <-0.19). CONCLUSIONS: The results do not suggest intrauterine environment influences physical activity in children. Further research is warranted on this issue in a larger sample with direct measurements of maternal health status during pregnancy.