If you’ve ever wondered how long sperm can live, you’re not alone. Most men (and women) know very little about how long sperm remains potent after leaving the body. But understanding some basic information about the life span of sperm is important when it comes to preventing an unwanted pregnancy. Under the right conditions, sperm can live long enough to fertilize an egg up to a week after unprotected sex.
The life span of sperm depends upon the environment into which it’s ejaculated. Sperm thrives in warm, moist environments, making the vagina an ideal location for long survival. If sperm travels far enough into a woman’s body to reach the fallopian tubes, it can survive for up to seven days. However, if sperm makes it no farther than the vagina, the acidic environment will kill it within just a few hours. Depending on the distance it travels, three to five days is the typical life span for sperm inside a woman’s body.
Outside the vagina, sperm usually dies within a few hours because it’s usually ejaculated into a dry environment. Sperm cannot live if the semen has dried. However, if the sperm is ejaculated into a warm, wet environment like a bath or hot tub it can live longer. Factors like water temperature and the presence of soaps and chemicals will determine exactly how long sperm can survive in this case.
Finally, sperm that’s frozen, such as the sperm samples donated to sperm banks, can live indefinitely.