Although menopause occurs at different ages depending on the individual woman's body, the average age at which a woman enters menopause is 51, reports WebMD. Premature menopause happens before a woman turns 40.
Fertility does begin to decline before menopause occurs, notes WebMD. It typically begins to decline more rapidly in her late 30s, but many women are still able to reliably conceive until about age 41. However, there are many factors that can influence individual fertility, so these numbers may vary considerably between individuals. Women are also still able to get pregnant in the first stage of menopause, known as perimenopause. During this phase, the woman still menstruates, but her cycles become irregular.
Pregnancies in older women, especially during perimenopause, may be more difficult to carry to term, reports Everyday Health. These women may be more likely to develop complications, and the eggs are usually of lower quality. This significantly increases the chance of miscarriage.
Although pregnancies during perimenopause are rare, women who do not want to become pregnant should continue to use birth control until they have not had a period for at least a year, suggests Everyday Health. This means that menopause has occurred, and the woman is no longer fertile. However, women who have experienced menopause can sometimes still become pregnant through the use of donated eggs and in-vitro fertilization.