These parts are the vagina, cervix, uterus, fallopian tubes, and ovaries. Your vagina connects your vulva to the reproductive organs inside your body. Look at the drawing of the reproductive organs to see how these parts fit together. Your period will begin when these parts have grown up. Sometimes a girl's reproductive organs grow up before she does.
Girls have two ovaries.
Each one holds hundreds of thousands of very tiny eggs. The eggs are so tiny you can't even see them without a microscope. Girls are born with all the eggs they will ever have. An ovary releases one egg about once a month. Before the egg is let go, the uterus begins building up a lining.