Pregnant women shouldn’t take a bath that’s hot enough to raise their core body temp to 101-102°F for more than 10 minutes. Why? Exceeding a body temp of 101°F or 102°F (there’s debate over this number among experts) can cause a condition known as hyperthermia, a condition in which the body absorbs more heat than it repels. Studies have linked a high core body temperature, especially early in pregnancy, with neural tube defects like spina bifida.
Unless you’re a fan of near-scalding baths or your tub retains heat well, you likely have nothing to worry about. But to avoid any issues, keep the temperature of the water warm enough to be comfortable, but not so warm that it causes you to sweat or your skin to turn red. You’ll know that your core body temperature is rising if you’re feeling flushed or sweaty. If that happens, get out of the tub and let the water cool.
While prepping for that warm bath, skip the bubbles and scented oils and salts, as they can alter the vagina’s acidic balance, which can cause thrush, a common yeast infection. While thrush is treatable, not all treatments may be safe during pregnancy, so talk to your health care provider. A mom who has a thrush infection at the time of delivery can pass it along to her baby, but babies can be easily treated.