Whether you’re trying to achieve or avoid pregnancy, knowing how long sperm can live once ejaculated is an important question to answer. Sperm can live outside the body for varying amounts of time, depending on several factors, including the environment (ie: cervical mucus, where they end up…) (9). Here we’ll talk about how long sperm can live inside the female reproductive tract, on the skin, and other surfaces.
Inside the vagina
The lifespan of sperm inside a woman’s body is under debate, but experts agree that it depends on cervical mucus, which provides the sperm with the nutrients and the medium they need to survive during their journey to the ovum (3). Sperm can be damaged by the vagina’s natural acidity, which protects against foreign bacteria (16). But in the right conditions, sperm can even live up to 5 (8) or 6 days in your body after intercourse (1, 10). This is an incredible feat compared to the brief lifespan of a mere few hours when no cervical mucus is present (4). In addition, a couple older studies suggest that the lifespan of sperm within a woman’s body also depends on the type of natural flora that’s present in the reproductive tract (5, 6).
This is part of why tracking cervical mucus is crucial to understanding your fertility. With nutrient-rich, fertile cervical mucus, sperm can live longer in the woman’s body and have more time to reach the egg or simply hang out until the egg is released. Studies show that if sperm enters the vagina when cervical mucus is most fertile a few days before ovulation, pregnancy is not only possible but actually more likely (7, 16).
In short, how long sperm can live inside a vagina depends on the conditions when it made its way in there and the type of cervical mucus (if any) that’s present. Tracking your cervical mucus is a great way to understand your fertility and to achieve or avoid pregnancy. Check out this blog about charting cervical mucus to get pregnant for more information.
If you’re using withdrawal as a method of contraception, ejaculation should be aimed far away from the vulva. Otherwise, it is possible that sperm on the vulva or even the upper thighs could navigate their way into the vagina and cause pregnancy (11). But once sperm has dried, it is dead and cannot cause pregnancy even if it is re-moistened (12), in the shower, for instance.
Sperm is extremely sensitive to temperature and needs specific conditions to survive, including the right temperature (13) and pH (14). Sperm usually cannot survive the temperatures or chemicals in chlorinated pools or Jacuzzis (12, 15) and will die within seconds; though sperm could survive a few minutes in plain (no soap, bath salts, etc.), warm bath water, a pregnancy resulting solely from bath water with sperm in it when no intercourse has occurred would be highly unlikely (9). If intercourse does happen in the shower, bath, or pool, pregnancy is just as likely to occur since the sperm would be able to enter the female reproductive tract directly (9).
Semen can end up on a variety of other surfaces depending on where your activities take place, but just remember, as soon as it dries out, it is dead and will not become viable again even if it's rehydrated (12).