Maternal Exercise and DHA Levels During Pregnancy Influences Infant Body Composition

Infant heart rate(HR) and heart rate variability(HRV) are used to estimate nervous system development and overall well-being of the fetus. Exercise during pregnancy is associated with improved infant HR and HRV. Similarly, DHA supplementation during pregnancy has also been shown to improve infant HR and HRV. However, there has not been any observation of the potential relationship between exercise intervention and maternal DHA levels on Infant HR and HRV. PURPOSE: To determine the relationship between maternal exercise and plasma levels of DHA on infant nervous system development, estimated by measures of HR and HRV. METHODS: Maternal plasma collected at 16 and 36 weeks of gestation were processed using solid phase extraction and analyzed using liquid chromatography/triple quadrupole mass spectrometry (LC/MS) to measure DHA levels. Samples were analyzed from 3 exercising (>50min aerobic exercise, 3x week) and 2 non-exercising pregnant women; average weekly METs were calculated based on standard MET values for each exercise activity. Infant HR and HRV were measured 1 month after birth. T-tests determined significance between groups; relationships between variables were tested with ANOVA and linear regression. Our p-value is set at 0.05. RESULTS: There were no significant differences between groups in infant HR (p=0.35, F=1.208) or 36 week plasma DHA levels (p=0.57, F=0.407). Linear regressions demonstrated negative relationships between Maternal average METs and Infant HR (r2=0.312) and 36 week maternal DHA levels and Infant HR (r2=0.156), as well as positive relationship between average METs and 36 week plasma DHA levels (r2=0.029). Multiple regression analysis of maternal average METs and maternal DHA levels to Infant HR was also determined (R2=0.404). Maternal average METs was the stronger of the predictors for Infant HR. CONCLUSION: The current data support the relationship between maternal exercise and DHA levels on infant HR. This is the first study to examine maternal exercise and DHA levels during pregnancy and infant heart outcomes. Further samples will be analyzed to confirm the relationship between maternal exercise, maternal DHA levels and infant outcomes.