Ovulation refers to the 3 days before and 4 days after the day of ovulation. Since ovulation represents a long period of time, the chances of pregnancy can vary from time to time. On the first 1-2 days after ovulation, the chances of pregnancy can be as high as about 50% if you ejaculate inside the body on the day of ovulation, and more than 90% if you ejaculate inside the body on the day of ovulation. If you ejaculate internally on the last day of ovulation, the chances of pregnancy are significantly lower, mostly less than 40%. The chances of conception are highest within 24 hours after the elimination of the egg, and gradually decrease with time.