Some women enter medical menopause earlier if they’ve had their ovaries removed as a method of cancer prevention, Dr. Seibel adds.
You’ve officially reached menopause when you haven’t had a period for 12 months — at that point, you have a 0 percent chance of getting pregnant naturally. But your fertility declines for years leading up to menopause and in fact even earlier.
Women are born with all the eggs they’ll ever have, but that reserve declines over time, says Seibel. With age, fewer healthy eggs survive in the ovaries. The overall health of those eggs declines, too, making it harder to get pregnant naturally during perimenopause, says Monica Christmas, MD, a board member of the Menopause Society, an associate professor of obstetrics and gynecology, and the director of the menopause program at UChicago Medicine. Eventually, ovulation slows and stops completely.
The menopausal transition isn’t linear: Fertility may be trending downward, Seibel says, but women may still have one or two healthy eggs. Occasionally, women think they’re no longer fertile and are surprised to discover they’ve gotten pregnant, he adds.