Ck 12: Life Science: Human Egg Cells

[Free Registration/Login may be required to access all resource tools.] When a baby girl is born, her ovaries contain all of the eggs they will ever produce. But these eggs are not fully developed. They develop only after she starts having menstrual periods at about age 12 or 13. Just one egg develops each month. A woman will release an egg once each month until she is in her 40s. Learn more about human egg cells in this learning module produced by CK-12.