Growing up and making babies - puberty

Puberty is the name given to the physical and emotional changes which take place in most boys and girls between the ages of 10 and 14. Puberty occurs so that one day the boy or girl will be able to make a baby.

Reproduction, the technical term for making babies, can only occur when a boy and girl are sexually mature. One of the main physical changes of puberty is the growth and development of the sex organs the parts of the body that are used to have sex and make babies. Sex organs that can be seen on the outside of the body are called ‘genitals’ while those that are inside the body are usually called ‘reproductive organs’.
Some more about a girl’s sex organs
A picture of a girl's sex organs, including pubic hair, Labia, Vaginal Opening, Clitoris, Urethal opening, Hymen and Anus

Between a girl’s legs there are three small holes. At the front is the urethral opening which a girl urinates through, and at the back is the anus which she defecates from. In between these two holes is a third hole, her vaginal opening. From the vaginal opening there is a small passageway or tube, called the vagina, which leads to the reproductive organs inside the body.

When a girl has her period the blood comes out through her vagina. Inside the vagina there is a small piece of thin skin called the hymen. The hymen partly covers the vaginal opening, but there is still enough of a gap for blood to get through. Sometimes the hymen breaks and bleeds slightly when a girl has sex for the first time.