Women and their eggs: How many and for how long?
Originally Published: February 4, 2000 - Last Updated / Reviewed On: January 19, 2007
How many eggs does a woman have when she is born? Does a woman still have eggs when she starts menopause?
Unlike men, who produce new sperm daily throughout most of their lifetime, women are born with all their eggs in one — okay, two baskets (ovaries). To be more precise, a woman is born with about one to two million immature eggs, or follicles, in her ovaries.
Throughout her life, the vast majority of follicles will die through a process known as atresia. Atresia begins at birth and continues throughout the course of the woman's reproductive life. When a woman reaches puberty and starts to menstruate, only about 400,000 follicles remain. With each menstrual cycle, a thousand follicles are lost and only one lucky little follicle will actually mature into an ovum (egg), which is released into the fallopian tube, kicking off ovulation. That means that of the one to two million follicles, only about 400 will ever mature.
Relatively little or no follicles remain at menopause, which usually begins when a woman is between 48-55 years of age. The remaining follicles are unlikely to mature and become viable eggs because of the hormonal changes that come along with menopause.