Amber Patterman1, John P. Porcari1, Elizabeth Schwab1, Scott Doberstein1, Salvador Jaime1, Carl Foster1. Safety of Hot Yoga in Pregnant Women. 1Department of Exercise and Sport Science, University of Wisconsin-La Crosse, La Crosse, WI, USA.


Introduction: One of the concerns surrounding the practice of hot yoga is a potentially dangerous increase in core temperature, particularly in pregnant women. Previous research has shown that a core temperature in excess of 102°F, or an increase in core temperature greater than 3°F from rest, may result in abnormal fetal development. Purpose: The main purpose of this study was to evaluate and compare core temperature responses in pregnant and non-pregnant women during a 60-minute hot-yoga class. Methods: Four pregnant and five non-pregnant women served as subjects. All were regular participants in hot yoga. Prior to the class, subjects ingested a CorTemp Ingestible Core Body Temperature Sensor (HQ Inc, Palmetto, FL). Core temperature was recorded every 10 minutes during the class. Results: Room temperature and humidity during the class averaged 95.7°F and 56.7% respectively. The highest core temperature recorded during a class averaged 99.5°F in the pregnant subjects and 99.9°F for the non-pregnant subjects. The highest single core temperature in a pregnant subject was 100.1°F, while one non-pregnant volunteer reached 101.4°F. None of the pregnant subjects had a change in core temperature during a class in excess of 1.2°F and the largest change for a non-pregnant subject was 2.8°F. Conclusion: Based upon the results of this study, it appears that women who are participating in hot yoga prior to their pregnancy can safely continue their practice. The ultimate decision, however, should be a joint decision with the expectant mother and her health care provider.