Can I Hot Tub While Pregnant?
Chemicals vs. Heat
There’s a common misconception among pregnant women that the chemicals used to maintain clean hot tub water are the reason they shouldn’t be enjoying a late night dip. That’s simply not true. If the hot tub water is balanced (especially the pH), there’s nothing harmful for a pregnant woman to sit in.
The main issue with using a hot tub while pregnant is the heat. Most hot tub units come factory programmed at 104° Fahrenheit. At this temperature, it takes the human body only 10-20 minutes before its normal core temperature of 98.6° elevates to 102° or higher, putting it in a state of hyperthermia (the opposite of hypothermia). Any body temperature over 101°-102° Fahrenheit can cause problems in a woman’s pregnancy.
Research has shown that high heat from fever, hot baths, or hot tubs can cause birth defects, particularly during key times in the fetus’ development. One of the most common birth defects are NRD or neural tube defects. Women are most susceptible to neural tube defects and miscarriage in the first trimester of their pregnancy. It’s at this time that women should be most careful in and around excessively hot water.
According to Catherine Lynch, OB-GYN, “We know that water over 105 degrees is damaging to developing cells. It won’t damage yours, but the baby is sitting in fluid that is also going to get very warm. And extreme temperatures can damage early embryos. So hot-tubbing in the first trimester could cause malformations in the fetus or cause you to lose the baby.”
Just like Dr. Lynch said, developing cells are damaged when they are exposed to high temperatures. Neural tubes are particularly at risk because neural tube defects occur when cells are trying to change shape and form a neural tube but cannot close completely. The risks for NTDs to occur is about 2-4 times higher when a mother in her first trimester overheats either from external heat (hot tub, sauna, heat stroke) or internal heat (fever). While you may not be able to prevent the latter, you do have some control over the former.
Other things that develop in the first trimester are the facial features and organ systems. These could also be adversely affected by elevated temperatures for extended periods of time. According to OB-GYN Dr. Jeanne-Marie Guise, “Soaking in hot water or sitting in a hot, steamy room can make you overheat, which raises your heart rate and reduces blood flow to your uterus, potentially putting your baby under stress or interfering with normal development. And because pregnant women have a hard time cooling down, you’re more likely to pass out if you get overheated in a hot tub or sauna.”
Safe Hot Tub Usage
If you own a hot tub and can control the temperature and environment you’re soaking in, you can make a few adjustments to make the hot tub safer for you during your preganancy:
Talk to your doctor—ALWAYS ask your doctor before doing anything different in your routine. They will know your specific risk factors and have all the information to recommend or discourage a particular activity. Don’t go against your doctor’s advice.
Bring the temperature down—Reprogram your hot tub to a lower temperature, preferably to 100° F or lower. This makes it more like a bath than a true hot tub soak, but it’s a good way to get more time in the water. Use a thermometer in your hot tub water to make sure it stays at a safe level.
Avoid the hot tub during your first trimester—As we’ve outlined above, the first trimester is when you’re at the greatest risk of affecting your baby in utero. You’re essentially out of the woods after 12-16 weeks.
Keeping your chest out of the water—This helps you regulate your body temperatures much more effectively. You could even use a kickboard or pool noodle under your lower back so your chest and stomach stay mostly out of the water while your back and legs still get soothed by the heat. You’re less likely to overheat if your entire body isn’t submerged in the water.
Limit your time—It’s best not to spend an extended amount of time in the water when you’re pregnant. Most advice we’ve found from doctors suggest not staying in the water longer than 10-15 minutes. Set a timer on your phone if you have it nearby or have someone remind you when you’ve soaked for a set amount of time.
Pick your spot—The water is usually the hottest in a particular inlet that provides the newly heated water. Position yourself in the water where you’re furthest from this water so it’s not hitting you directly.
Listen to your body—If you stop sweating, feel light-headed, or are noticeably uncomfortable in the water, this might be your body telling you that your body temperature has risen to unsafe levels. Get out of the water immediately if you have any of these symptoms. In addition, keep a cold bottle of water nearby so that you stay hydrated.
Don’t get in if you’re ill—You should stay out of the hot tub if you aren’t feeling well or have an elevated temperature due to fever, exercise or heat stroke. Let your body regulate its temperature naturally and don’t try to cure the chills or cold symptoms with hot tub usage. Only use it when you’re feeling normal.
If you feel better about avoiding hot tub usage altogether, just take a bath; warm baths have much less inherent risk.
Again, if you have any other questions, consult your physician. Hopefully this has been a good jumping off point for information on using a hot tub while pregnant.