You develop breasts during puberty. This could start in a girl of 8, but also in a girl of 14.
Shape and size
Breasts come in all shapes and sizes. Nipples also differ greatly from each other, both in size and colour. Often one breast is bigger than the other is, or has a different shape.
In your genes
Your genes determine the shape and size of your breasts. If the women in your family have large breasts, then you will probably develop large breasts too. If they have small breasts, then you usually develop small breasts too.
Lots of girls are unhappy with their breasts. They would like larger, smaller or firmer breasts. But you can't change the shape and size of your breasts. And who’s to say which ones are actually prettier.
Your breasts consist mainly of mammary glands and milk ducts. These end at the nipples. They are responsible for milk secretion when you get pregnant. In addition, your breasts are composed of fatty tissue.
The breasts, influenced by hormones, prepare for pregnancy once a month. They get bigger and more sensitive. After your menstruation, they return to their old shape.
Breasts and sex
Lots of women like their breasts and nipples being touched when having sex. This could be with fingers, lips, teeth or a tongue. Your nipples get harder and bigger when you are turned on. The area surrounding your nipple swells up, darkens in colour and becomes lumpy.