What does it take to impregnate a woman?

For a woman to be impregnated, she must be ovulating, according to Planned Parenthood. Sperm must meet the egg in a process known as fertilization. A woman is impregnated if the fertilized egg implants in the woman's uterus.

Women have their periods for about three to seven days during the first two weeks of their menstrual cycles, Planned Parenthood notes. After the first two weeks, the lining of the uterus begins to thicken in preparation for a possible pregnancy. When a woman ovulates, she may become pregnant if sperm are present at the time an egg is released. Sexual intercourse that takes place in the five days before release of an egg or on the day the egg is released is most likely to result in pregnancy.