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Teen Physical and Sexual Development


Updated February 18, 2012

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Puberty Teens
Getty Images / Tony Latham

The biggest factor in the physical and sexual development of a teenager is the onset of puberty. Puberty is the time when the child becomes physically able to reproduce. Puberty has a hand in all of a teen's development.

In girls, puberty normally happens around the age of 11; in boys, around the age of 13. It is important to note that the age in which your teen starts puberty can vary between the ages of 9 to 14 years old. Some studies suggest the normal age of onset may even be earlier than that, and may differ among racial and ethnic groups.

During puberty your teen will experience growth of their genitals, pubic and body hair growth, body growth and changes in their skin and hair, which may become oily. They may develop acne or body odor. During this time, teens become self-conscious about their appearance and will wonder if they are normal. Much of these inadequate feelings are because their friends are developing at a different rate than they are and your teen is becoming more socially and emotionally aware at this time.

Assure your teen that he or she is growing normally. It is typical for teens to grow at different rates, and they will not look the same as their friends even when they are done growing. Every human being is unique; that is the one thing we all have in common.

Parents will notice that the physical changes in their teen son or daughter during puberty is rapid. It is, in fact, the fastest your child has grown since infancy. I remember a time when I bought my oldest daughter a new pair of sneakers for school in September. At the end of October - the very next month - we went hiking and I noticed she had a hole in her sneakers and her toe was sticking out. I asked her why she was wearing her old sneakers, and she informed me that she wasn't, that these were her new sneakers. We went that week to buy another pair - she had grown two sizes in just that little bit of time.

Therefore, do not be shocked if it seems that your teen has grown overnight. Even when I expect that my teens will grow in spurts like this, I am always taken by surprise when it happens.

It is important during this time of rapid growth that your teen is getting enough sleep, exercise and good nutrition. The more you focus on wellness practices, the more your teen will see the healthy benefits.

For instance, a teen who has gotten a good night's rest will not be as moody in class and will learn the lesson being taught. If your teen is not getting enough sleep at night, they may fall asleep in class and their grades will suffer. Yes, this is easier said than done as teens like to stay awake later at night and sleep during the morning hours. But everyone has responsibilities, your teen included. So you will need to help your teen develop a relaxing nighttime routine so they can get to sleep as early as they need to.

When Physical and Sexual Development in Teens Is Not Normal

There are times when the physical and sexual development in teenagers is not normal. The most common problems are precocious or early puberty and delayed puberty. While there are medical reasons for these abnormalities, the most important thing for parents to know is that you need help at this point. If your teen develops signs of puberty around the age of 9 or younger, you will want to get them an appointment with their pediatrician. The same is true if you see minimal or no signs of puberty by the age of 13.

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