When the time is right for you, your body sends a signal from your pituitary gland in your brain to your ovaries for puberty to begin. During puberty, your body is going to change.
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 on 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.
Pubic and underarm hair. You will start to grow hair around your pubic area (around your vagina) and under your arms. This usually happens after you start to develop breasts, but for many girls, pubic hair starts first. You will probably get pubic hair before you get underarm hair. Underarm hair usually comes near the end of puberty. At first, you will probably just have a few fine hairs in your pubic area and under your arms. Late in puberty, the hair will become thicker and curlier. Some girls decide to shave the hair under their arms. There are no health reasons to do so, but some girls simply prefer not to have underarm hair. It is up to you if you want to shave. Talk to your mom or another adult that you feel comfortable talking to about this
Growth spurt and body shape change. Most girls have a growth spurt the year before they get their menstrual period. Your feet and hands will usually be the first parts to grow, and then the rest of your body will follow. After you get your first period, you will grow more slowly. But you will probably grow about another 1 or 2 inches after your first period. During puberty, your hips will get wider as your waist gets smaller. You will develop a healthy, curvy shape. Talk to your health care provider if you are not growing and changing by age 13. It’s important to get check-ups during puberty to make sure that your height and weight are normal.
Vaginal discharge. Most girls notice a yellow or white stain in the crotch of their underpants as they go through puberty. This is a normal fluid that helps clean and moisten your vagina. However, if you have itching, odor, or irritation around your vagina, this could mean that you have an infection. If you have any of these symptoms, talk to your health care provider. You will usually get your period a year after you first have discharge from your vagina.
Skin. Your skin may get oilier. You may get some pimples and acne. This is because of more hormones and oil glands that become more active during puberty. You should be washing your skin at least once daily with soap and warm water. Don’t scrub too hard because this can irritate your skin and cause even more acne. Wash your hair regularly and keep your face and hands clean. You can treat acne with medications that you can buy in a drugstore, or get from your primary care clinician or a dermatologist (a doctor that treats skin problems) if the problem is more serious. Birth control pills that you take by mouth often make acne better.
Sweat/Perspiration. Your sweat glands will become more active during puberty. This can cause perspiration odor. This is a good time to go shopping for deodorant, to help fight the odor.
Menstruation. You will also start getting your monthly menstrual period. Most girls start getting their menstrual periods about 2 and a half years after they first start developing breasts. Most girls have their first menstrual period between the ages of 12 and 13, but some girls start as early as age 9 and others as late as 15 or 16.