Influence of maternal aerobic exercise during pregnancy on fetal cardiac function and outflow

Abstract

BACKGROUND: Risk factors for cardiovascular disease, the leading cause of death, have been documented in children as young as 3 years of age. Maternal environment (eg, exercise) influences fetal development and long-term health. Thus, the development of the fetal cardiovascular system during pregnancy is likely a preliminary indicator of cardiac health at birth and a proxy for the future risk of cardiovascular disease throughout life. OBJECTIVE: The purpose of this study was to assess the effects of supervised prenatal aerobic exercise at recommended levels on fetal cardiac function and outflow in the third trimester of pregnancy. We hypothesized that fetuses of aerobically trained women compared with fetuses of nonexercising women would exhibit increased cardiac function and greater cardiac output. STUDY DESIGN: Secondary data analyses of a 20-week, randomized controlled exercise intervention trial in pregnant women between 2015 and 2018 in Eastern North Carolina were performed. Eligibility criteria included pregnant women <16 weeks gestation, singleton pregnancy, aged 18e40 years, body mass index of 18.5e34.99 kg/m 2 , physician clearance letter for exercise participation, reliable transportation, and method of communication. Exclusion criteria included the presence of chronic conditions (eg, type 1 or 2 diabetes mellitus), current medications known to adversely affect fetal growth (eg, antidepressants), alcohol, smoking, or illicit drug use. The patient cohort consisted of 133 eligible pregnant women who were assigned randomly to either an aerobic exercise (n¼66) group that participated in 150 minutes of supervised, moderate-intensity (40-59% VO 2peak ; 12e14 on Borg Rating of Perceived Exertion) aerobic exercise per week or a nonexercising group (n¼61) that consisted of 150 minutes per week of light (<40% VO 2peak ) stretching and relaxation breathing techniques. Between 34 and 36 weeks gestation, a fetal echocardiogram was performed to assess fetal cardiac function, which included fetal heart rate, right-and left-ventricular stroke volume, stroke volume index, cardiac output, cardiac output index, and cardiac outflow that included pulmonary and aortic valve diameters, peak flow velocity, and peak flow velocity-time integral. Fetal activity state (quiet vs active) during the echocardiogram and maternal aerobic capacity served as covariates. Intention-to-treat and per-protocol (participants who attended !80% of exercise sessions) analysis of covariance regression models were performed. RESULTS: Of the 127 randomly assigned participants, 66 and 50 participants were included in the intention-to-treat and per-protocol analyses, respectively. Prenatal aerobic exercise significantly increased fetal right-ventricular cardiac measures of right ventricular stroke volume (P¼.001) and stroke index via velocity-time integral (P¼.003), right ventricular cardiac output (P¼.002), cardiac index via velocity-time integral (P¼.006), pulmonary artery diameter (P¼.02), and pulmonary valve velocity-time integral (P¼.03). Only in ...

Influence of Light Intensity exercise During Pregnancy on Fetal Echocardiographic and Maternal Cardiovascular Measures

“…These findings align with earlier research that shows a dose-response relationship between maternal exercise intensity and offspring cardiac adaptations [9,23,46,47]. Though the differences compared to controls in fetal flow velocities were not as large in this analysis, the findings are similar to the significant left ventricular flow velocity observed in fetuses exposed to moderate intensity aerobic exercise [1]. Importantly, left ventricular outflow measures are thought to contribute to the atherosclerotic environment [48] and are a better predictor of adverse cardiovascular outcomes than left ventricular ejection fraction [38].…”

“…Exercise duration influenced fetal right ventricular outcomes. Comparable to differences in fetal heart measures due to supervised, moderate intensity maternal exercise [1], light intensity exercise at the recommended duration of 150 minutes each week influenced fetal right ventricular heart outcomes. Potentially due to the lower energy expenditure associated with lower intensity, a longer duration of lower intensity may elicit a similar response as the 150 minutes of moderate intensity exercise [21].…”

“…Although exercise at recommended levels of 150 minutes/week, moderate intensity during pregnancy demonstrates maternal and fetal benefits and decreased gestational conditions [1][2][3][4][5][6][7], more than half of pregnant women fail to meet the recommended levels of prenatal physical activity [8]. While research demonstrates maternal exercise has a dose response with fetal heart outcomes [9] and light intensity (LI) exercises is one way to decrease sedentary time, research shows this to be a preference for Hispanics, black, and obese pregnant women [10][11][12].…”

Maternal Low Volume Circulation Relates to Normotensive and Preeclamptic Fetal Growth Restriction

“…Lower systolic blood pressure was also observed in trained versus non-trained normotensive pregnant women ( 141 ). Importantly, maternal physical training was shown to influence fetal cardiovascular functions by the increase of left ventricular output and aortic peak flow velocity ( 142 ) and by lower carotid artery wall thickness in offspring ( 143 ).…”

Measuring Mitochondrial Electron Transfer Complexes in Previously Frozen Cardiac Tissue from the Offspring of Sow: A Model to Assess Exercise-Induced Mitochondrial Bioenergetics Changes

“…Nevertheless, aerobic exercise-induced positive changes in fetal myocyte bioenergetics during pregnancy are yet to be documented. However, emerging studies provide evidence that maternal aerobic exercise during pregnancy has a positive influence on fetal cardiac function 5 . In order to provide further evidence, an analysis of the longitudinal effects of maternal exercise on offspring cardiac mitochondrial respiratory chain complexes (i.e., Complex I through Complex V) during pregnancy was performed.…”