why does semen leak out of the vagina after sex? the real answer: it has nowhere else to go. at the end of the vaginal canal is the cervix, which essentially blocks the fluid (or anything else) from getting up into the uterus. because of that, what goes up (or in), must come back down. it is completely normal to 'leak' semen for a few hours, even up to a day, after someone has ejaculated inside of your vaginal canal. if this bothers you, you can use a dripstick to soak up the semen in the vaginal canal immediately after sex.