Practiced at 35 – 40 degrees Celsius, hot yoga exposes pregnant women and their foetuses to excessive heat. The excessive core body temperature can cause maternal hyperthermic, which in the first trimester, has been shown to increase the risk of neural tube defects in animals and humans.
In the latest edition of Canadian Family Physician, researchers write:
“With the increased risk of neural tube defects and possibly of other malformations among fetuses exposed to excessive heat, pregnant women should avoid practising hot yoga during pregnancy.”
There are currently no published studies examining the safety and outcome of hot yoga on pregnant women and their foetuses. There is also a lack of consensus among yoga clubs about allowing pregnant women into their hot yoga sessions.
Dr. Gideon Koren, director of Motherisk and the leading author said:
“Yoga, per se, is not the issue. It’s the heat newly pregnant women should avoid.”
Dr Koren’s recommends that women avoid hot yoga during their first trimester. Hot yoga is safer in the second and third trimester – unless the woman has other restrictions related to heat exposure, such as low or high blood pressure, fatigue, a chronic illness or severe morning sickness.
According to Koren’s group, excessive heat exposure might cause dizziness or fainting because blood pressure tends to be lower in the first trimester of pregnancy.