Fetal and Maternal Responses to Yoga in the Third Trimester [30F]

Abstract

INTRODUCTION: The goal is to examine the practical and real-time maternal and fetal responses to a moderate intensity yoga session in the third trimester of pregnancy. Unlike previous studies, our study examines a typical 1-hour, moderate intensity prenatal yoga session. METHODS: This is a prospective observational study in low-risk, pregnant participants. Exclusion criteria included hypertension, IUGR, preterm labor, or contraindications to exercise. Wireless fetal monitors were used to monitor fetal beat-to-beat variability, accelerations, and decelerations as well as maternal heart rate and uterine activity. For analysis, fetal and maternal heart rates were continuously recorded over the entire yoga session, and pre- and post NST tracings were analyzed for loss of fetal heart rate variability and decelerations. RESULTS: Twenty participants were enrolled; 19 completed the session. Mean gestational age was 35 weeks and 6 days with an average participant age of 32 years. While fetal heart rates fluctuated over the course of the yoga session, there were no significant fetal heart rate decelerations or changes in beat-to-beat variability to suggest deleterious fetal effects. The fetal heart rate averaged 135.3 bpm (SD±12.2) regardless of activity level . Maternal heart rate also fluctuated from a mean resting heart rate of 88.7 bpm (SD±9.7), increasing to an average heart rate of 104.8 bpm (SD±18.6) during the session, reaching a maximum of 154.9 bpm (SD±12.8), and subsequently decreasing to 88.7 bpm (SD±11.2) during meditation,. CONCLUSION: Yoga can be recommended for low-risk women during pregnancy as no adverse fetal heart rate effects were observed during a realistic, continuous yoga session.