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Puberty is the name for the time when your body goes through changes and you begin to go from being a child to an adult. Your hormone levels will change, you will develop breasts, grow taller, and start your menstrual periods. Puberty usually starts between 8 and 13 years of age. During puberty, the same changes happen to all girls, but the time they happen is different for every girl. These changes are all part of becoming a woman. They are something to celebrate!
When the time is right, your body sends a signal (FSH, LH) from the pituitary gland in your brain to your ovaries for puberty to begin.
Breast development: Your breasts will start to grow. Your breasts will start as breast “buds”, small mounds beneath the nipple and areola. (The areola is the dark area surrounding your nipple.) One breast may start growing before the other, sometimes even 6 months before the other. In the beginning, they may hurt sometimes and be tender when they are touched. But this will go away as your breasts become rounder and fuller. The nipple and areola also darken. Many girls have breasts that develop unevenly; one breast may be bigger than the other. This is perfectly normal. Many women have one breast that is slightly larger than the other, but the difference in breast size usually decreases as your breasts develop. Young women may have different breast sizes because of differences in families, hormones, and weight. Rapid development of breasts can lead to spoke-like stretch marks, but these will lighten with time. Towards the end of puberty, you may also grow a small amount of hair around your areola.
You may need to start thinking about wearing a bra to support your breasts. Talk to your mother, an older sister, or an adult that you feel comfortable with about buying some bras.
Meanwhile don't unnecessarily pinch or squeeze your breasts, you may hurt yourself. If they give you pain, remember to have a warm wet towel on the area. You will get over these symptoms soon. Enjoy, welcome to womanhood. Good luck