Of the original 2 million egg cells only 40,000 are left when a girl reaches puberty. And only 400 of them, usually one every month, will develop fully. Just before ovulation several egg cells are in the process of ripening in the ovaries, and soon the most mature egg follicle ruptures and the egg is released into the Fallopian tube. It takes a sperm 30 minutes to 48 hours to reach the egg. During the next couple of days you may get pregnant.