How likely am I to get pregnant by having intercourse on the last day of my period?

It’s possible to get pregnant any time you have unprotected sex, regardless of what day it is in your cycle. Sperm can live in a woman’s reproductive tract for about six days, so it’s always best to use protection. It’s more likely that you’ll get pregnant from intercourse on the last day of your period if you have a shorter menstrual cycle. Your body ovulates — releases an egg from your ovaries — about 14 to 16 days before your period. If your cycle is only about 22 days long, sperm that entered your vagina on the last day of your period could still be there when you ovulate.

The morning after pill (also known as emergency contraception) is a safe and effective way to prevent pregnancy after unprotected intercourse. It can be started up to five days (120 hours) after unprotected intercourse.

The brands Plan B One-Step and Next Choice are available from drugstores and health centers without a prescription only. If you are interested in getting emergency contraception and are 17 or older, you can either get it directly from a Planned Parenthood health center or private health care provider for a prescription.

The best way to prevent pregnancy is by using birth control. Learn more about your birth control options.