Cardiovascular adaptations to aerobic exercise in obese pregnant women : the ENHANCED by mom project

Abstract

Background: Hypertension is the most prevalent problem in pregnancy affecting 10% of pregnant women worldwide. Furthermore, obesity during pregnancy correlates with complications such as gestational hypertension. Aerobic exercise is considered to be the most commonly recommended exercise for pregnant women. This analysis is designed to evaluate cardiovascular outcomes and adaptations in pregnancy with an aerobic exercise dose. Objective: To compare the effects of aerobic training on cardiovascular adaptations and outcomes for overweight and normal weight pregnant women across gestation. Main outcome measures: Systolic blood pressure, Diastolic blood pressure and Heart rate at 16, 20, 24, 28, 32, and 36 weeks of gestation. Results: There is a significant difference in systolic blood pressure between normal and overweight(p=.001) participants at each time point. With aerobic exercise, overweight pregnant women had a higher systolic pressure over their normal weight counterparts, and this was sustained throughout pregnancy. The normal weight group had a sustained lower systolic pressure throughout gestation. When analyzing the diastolic blood pressure, it was not significant within the group across gestational weeks. (p=.41) Throughout pregnancy diastolic blood pressure was consistently higher in overweight women compared to the normal weight group. There wasn't a significant difference in heart rate between There wasn't a significant difference in heart rate between the normal and overweight groups (.09). Although it was not a significant difference between groups, the overweight consistently had a higher heart rate throughout gestation. Additionally, there is not a significant difference across time (p=.82) with the intervention of aerobic activity throughout gestation. Conclusion: With moderate intensity aerobic exercise, there were similar trends found in normal/overweight pregnant women in diastolic blood pressure and heart rate within gestation. The trend for blood pressure declined slightly from 16 weeks until 24 weeks gestation; at 24 weeks gestation blood pressure tended to increase slightly until delivery in both the normal and overweight groups with aerobic exercise. This may suggest a need for more of an exercise dose to attenuate the cardiovascular measures that increase during pregnancy, or a different mode of exercise such as circuit which involves both resistance and aerobic activity.