If you choose to use a hot tub or sauna while pregnant, follow this advice: lower the temperature to below 38.9°C (102°F); spend a maximum of only 10 minutes in a hot tub or 15 minutes in a sauna. Have another adult with you; and get out right away if you feel dizzy, faint, have a rapid pulse, irregular heartbeat, stomach pain, or tingling in your feet or hands. In a hot tub, sit with your arms and chest above the water.
Use of Hydrotherapy Pools during Pregnancy
As a precautionary measure the Royal College of Obstetricians and Gynaecologists (RCOG) suggests that where hydrotherapy pools are used during pregnancy, the temperature should not exceed 35°C.
There are limited data on most pregnancy outcomes following maternal exposure to external heat sources such as saunas, hot tubs, and hot baths. There are no data relating specifically to steam room exposure. Three out of the four case-control studies that have been carried out have reported that gestational exposure to hot tubs and hot baths might be associated with an increased risk of NTDs in the offspring.
Precautions During Pregnancy
Excessive heat and long soaks should be avoided during pregnancy as women may be at higher risk of overheating (hyperthermia). This can be harmful to the developing baby (fetus), particularly during the early weeks when organs are forming.
If you are pregnant and choose to use a hot tub (or sauna), take the following precautions:
- Lower the temperature to below 38.9°C
- Limit your time in the sauna to no more than 15 minutes and hot tub use to no more than 10 minutes, or less if you feel uncomfortable
- Sit with your arms and chest above the water
- Have another adult with you
- Get out right away if you feel dizzy, faint, have a rapid pulse, irregular heartbeat, stomach pain, or tingling in your feet and hands.
Exposure to external heat sources such as saunas, steam rooms, hot tubs, or hot baths at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy or any additional fetal monitoring. However, other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcomes. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.