There's little research on using saunas, jacuzzis, hot tubs and steam rooms during pregnancy. However, it's advisable to avoid them because of the risks of overheating, dehydration and fainting.
You're likely to feel warmer than normal during pregnancy. This is caused by hormonal changes and an increase in blood supply to the skin. These hormonal changes can also make pregnant women feel faint.
Overheating
When you use a sauna, jacuzzi, hot tub or steam room, your body is unable to lose heat effectively by sweating. Your body's core temperature therefore rises.
It's possible that a significant rise in your core temperature may affect your unborn baby's development, particularly in the first 12 weeks of pregnancy.
Feeling faint
If you overheat, more blood flows close to your skin to help cool your body by sweating. This means there's less blood flow to internal organs, such as your brain. If you don't get enough blood and oxygen to your brain, it can make you feel faint.
When you're pregnant, the hormonal changes in your body can make you feel faint more often. You therefore may want to avoid situations where you could get too hot, such as sitting in a jacuzzi or steam room.
Water temperature
The Royal College of Obstetricians and Gynaecologists recommends that if you're exercising in water – for example, at an antenatal class – the temperature of the water shouldn't be above 32C (89.6F).
If you're using a hydrotherapy pool, the temperature shouldn't be above 35C (95F). Some hot tubs can be as hot as 40C (104F), so it's best to avoid them.
Read more about exercising during pregnancy and get more answers to questions about pregnancy.
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