Yoga is very popular, both as a fitness exercise and for its relaxation benefits. Many yoga studios offer prenatal yoga classes geared toward pregnant women. But pregnant women have often been told to avoid certain yoga poses (also called asanas), especially later in their pregnancies. These include postures that involve lying on your back because they are thought to reduce blood flow to the uterus, which includes the “happy baby pose” and the “corpse pose.” Pregnant women are also often told not to use postures that have them partially or completely upside down, such as “downward facing dog.” These poses are thought to increase the fetal heart rate. But according to two recent studies, these postures appear to be safe, as is yoga in general during pregnancy.
To see if these postures really pose a problem, researchers at Jersey Shore University Medical Center in Neptune, NJ, monitored the heart rates of the babies while 25 healthy women in their final weeks of pregnancy assumed 26 common yoga poses. They also monitored the women’s vital signs and blood oxygen levels.
None of the women had any medical conditions that would make exercise more of a risk for them. Ten of the women were already regular yoga practitioners, eight were familiar with yoga, and seven had never done it before. Each woman had a personal one-on-one yoga session with a certified yoga instructor who led them through the 26 postures. None of the poses used involved either lying on the stomach or being completely upside-down.
The researchers, found that fetal heart rates remained normal through all of the poses. The women were also contacted 24 hours after their yoga session. None reported decreased fetal movement, contractions, fluid leakage, or vaginal bleeding in the next 24 hours, according to the study.
However, this is a small study and involved only healthy women without complications with their pregnancies. The study was published in the journal Obstetrics & Gynecology.
The second study, reported in the American Journal of Obstetrics and Gynecology, found similar good news for pregnant women about yoga. This one involved 52 women in late pregnancy who had never tried yoga. They were randomly assigned to either take part in a one-hour yoga class or to listen to a one-hour lectureon exercise, nutrition, and obesity in pregnancy.
These researchers, at medical centers in Virginia, Texas, and Kansas, found no significant change in fetal blood flow immediately after the women did yoga. This study concluded that healthy women could safely begin yoga during pregnancy.
1. Polis RL, Gussman D, Kuo YH: Yoga in pregnancy: An examination of maternal and fetal responses to 26 yoga postures. Obstet Gynecol. 2015 Dec;126(6):1237-41.
2. Babbar S, Hill JB, Williams KB, et al.: Acute fetal behavioral response to prenatal yoga: A single, blinded, randomized controlled trial (TRY yoga). Am J Obstet Gynecol. 2016 Mar;214(3): 399.e1-8.