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Teen Girls' Health

Girls and Puberty

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Girls, see if this sounds familiar. You look in a mirror one morning and notice you're taller -- and rounder. Through your nightgown, you see your breasts are bigger. You don't remember looking like that a few weeks ago! Over the next few weeks, you start noticing hair in places you've never had hair before. You've heard girls at school talk about getting their periods, and you wonder if that will happen to you soon. You feel ultraconfident, and then super sensitive -- all in the same day. What in the world is going on? Welcome to puberty.

Technically speaking, puberty is nature's way of transforming a child into an adult, all for the sake of reproduction. While both girls and boys go through puberty, girls reach puberty and sexual maturity at earlier ages than boys do.

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So what's causing all of these changes? Hormones! Actually, the female hormone estrogen is the main one that's triggering all the changes in your body. Let's look at some of the changes girls can expect at puberty.

Increase in Height and Weight

Starting at around age 9, girls begin to gain about 17% to 18% of their adult height. If someone has commented that you are "all hands and feet," it's true! Your limbs grow first, then your trunk. Most girls grow fastest about six months before they start their first period (menarche).

You'll probably gain weight in puberty -- most girls do. You may notice more body fat along the upper arms, thighs, and upper back. Your hips will grow rounder and wider; your waist will become narrower.

Your doctor will check your height and weight each year to make sure you are growing properly. If you are gaining weight too fast, you may need to increase your exercise and substitute fruits and vegetables for junk foods.

Puberty Breast Development

Breast development is an early sign of puberty in girls. This can happen before age 9 in some girls, but later in others.

If you are self-conscious, you might want to start wearing a "training bra," which is a soft bra with no real support. 

Talk to your mom, older sister, or an aunt about buying a training bra. They can help you to make sure you get one that is comfortable and that lets you feel confident in your clothes.

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