Information for Preteens:
Physical Changes for Girls
Puberty – it's a crazy time. Your body is changing and so is everything else. But, what is causing all these changes?
Well, you know how everyone says that puberty is all about raging hormones – and it's kind of true. Hormones that were hibernating suddenly awaken and signal your body to enter puberty.
You might think that means nothing…hormones, shmormones. But, those hormones cause all the changes that you might associate with puberty.
Physical Changes Timeline
Since there is so much going on, I've drawn up a time line so that we can go through the steps chronologically.
Puberty Event | Age at which it happens |
Growth of breasts | 8-13 |
Growth of pubic hair | 8-14 |
Body Growth | 9.5-14.5 |
First Period | 10-16.5 |
Underarm Hair | 2 years after pubic hair shows up |
Acne | Approx. same time as underarm hair |
One word of caution about my timeline: puberty is not always perfectly regular, so some girls will grow pubic hair before they develop breasts, and that is absolutely normal.
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Breasts
Breast development starts off between 8 and 13 years of age and continues through puberty. First, the flat area around the nipple (areola) becomes enlarged, and breast tissue forms under the nipple.
When breast development is complete, each breast is distinct and the areola no longer appears swollen. Breast size varies from woman to woman. You cannot change your breast size without plastic surgery, which is not always a very safe or healthy alternative.
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Pubic Hair
Pubic hair starts along the vaginal lips, the outer opening of your private parts. The hair becomes darker and coarser and grows like an inverted triangle. Sometimes, the hair spreads to the insides of your thighs as well.
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Growing
Puberty also causes you to go through a growth spurt, which results in an average growth of about 3.5 inches a year. The weird thing is that all of you doesn't grow at the same time. Your head, hands, and feet are the first things to grow; followed by your arms and legs; and finally your torso and shoulders.
Height growth is, of course, accompanied by an increase in weight. This weight gain is perfectly normal and a part of puberty. Without gaining this weight, you cannot grow taller, develop breasts, or get your first period.
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Sweat & Acne
Finally, underarm hair begins to grow. Your sweat and oil-producing glands also start developing, which eventually results in acne when these glands are clogged.
In order to avoid breakouts, you should wash your face twice daily and, if you regularly break out, it might be useful to consult a dermatologist.
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Katie Ransohoff,
high school student writer
Reviewed by: Adolescent Interest Group
Last reviewed: August 2013