This is very normal and let's talk about why. We need to get a little graphic, so bear with me. Ejaculate (the stuff that comes out when a man ejaculates) is made up of a lot of different things. One of its components is sperm. In a normal male ejaculate, there are anywhere between 20 and 400 million sperm. All you need to get pregnant is one. What normally happens after intercourse, is that a lot of the ejaculate does leak out. Some of it, however, remains in the back of the vagina (in the posterior fornix) and an even smaller amount makes its way up through the cervix, into the uterus and down the fallopian tubes. It is here, in the fallopian tubes, that the sperm and egg meet. So, the bottom line is that you don't need to lie in bed with your legs up after intercourse to get pregnant and the fact that semen is leaking out afterwards, doesn't decrease your chances of conceiving.