If you apply hot water to help relax stress on your ligaments and joints, don’t worry. It shouldn’t affect your pregnancy. Use a moderate amount of heat to the legs, arms, back or other parts of your body and the temperature won’t increase beyond the normal comfort level. Also, you can use electromagnetic heating pads, or electric heating pads without worry.
Saunas, or hot tubs, or even a hot bathtub can raise the body temperate beyond the comfort level for your baby and can cause catastrophic results to health and development. If your bath, hot tub, or sauna is over 40 degrees Celsius or 104 degrees Fahrenheit, it needs to cool down or don’t use it. This temperature is much too high and could overheat your new baby.