For healthy, young couples, the chances are about 20% that a woman will become pregnant during any one menstrual cycle. This figure starts to decline in a woman’s late 20s and early 30s and decreases even more after age 35. A man’s fertility also declines with age, but not as early.
Ovulation is the release of an egg from one of the ovaries. In an average 28-day menstrual cycle, ovulation occurs about 14 days after the first day of your last period. Once an egg is released, it is able to be fertilized for about 12-24 hours. Conception can occur if you have sex during or near the time of ovulation. After a couple has sex, the man’s sperm is released into the vagina and travel up through the cervix and out into the tubes. Sperm can live in the woman’s fallopian tubes for 3 days or more. If the sperm and egg join, fertilization occurs. The fertilized egg then moves through the tube into the uterus. It becomes attached there and begins to grow. All of these events must take place for pregnancy to occur. Infertility will result if any of these events fail to occur.