Two people could be arguing about whether or not you can get pregnant in a hot tub, and both could technically be correct. Somehow, there are two dominant myths pertaining to conception and hot tubs: The first is that, Virgin Mary-style, one could miraculously become impregnated while sitting in a hot tub that someone recently ejaculated in. The second is that the hot water and the chemicals of the hot tub make it impossible for someone to get pregnant while having unprotected sex in a hot tub.
Obviously, neither of those are true.
These myths involve some confusion about how both hot tubs and reproductive organs work. In the former myth, we seem to forget that hot tubs work by constantly circulating and replacing the water. Were someone to ejaculate in a hot tub, the contaminated water would be filtered out. Even if it didn’t, though, it still wouldn’t work to impregnate someone. Like the similar swimming pool myths, the sheer statistical improbability of a sperm cell being capable of entering the vagina and fertilizing an egg should be enough to shut it down. On top of that, though, the chemicals would indeed kill the sperm off.
The hot water, however, would only potentially damage the sperm. Without the chemicals, sperm could hypothetically live in warm to hot water for several minutes. In some cases, hot water has been linked to a reduced sperm count in men, but this is only temporary, and sperm counts should return to normal when testicle temperatures do the same. While this may reduce the odds of pregnancy, it doesn’t reduce them entirely, and because the vagina does not take in any of those hot tub chemicals, penis-in-vagina sex could certainly lead to conception.
As I wrote about swimming pool pregnancies, the laws of vaginas still apply in a hot tub: “If a person with a vagina goes swimming, their vagina doesn’t just fill up with water. The muscles of the pelvic floor and the walls of the vagina prevent this from happening. … If someone ejaculates directly into a vagina while in a pool, the semen will mostly remain in the vagina. Some might leak out –– the vagina isn’t airtight –– but most of it will remain inside. When the penis departs from the vagina, the pelvic floor will tighten and again keep the pool water from entering.”
There is one other hot tub/pregnancy-related myth that has some truth to it. Because of the potential risks of raising one’s body temperature above 102 degrees Fahrenheit during pregnancy, it’s often recommended that pregnant people avoid using hot tubs or taking excessively hot baths. Pregnant people can, however, somewhat safely use a hot tub if they’re able to properly monitor the temperature of themselves and the tub and ensure neither exceeds 100 degrees. On top of that, it’s important to monitor for signs of dehydration and overheating, as pregnant people are more likely to faint.
Maybe we all just got confused and the idea that pregnant people shouldn’t go in hot tubs translated into the idea that people in hot tubs can’t become pregnant… or can become pregnant, or something like that. Regardless, most of it isn’t even true.