For boys, the hormones travel through the blood and tell the testes, the two egg-shaped glands in the scrotum (the sac that hangs under the penis), to begin making testosterone and sperm. Testosterone is the hormone that causes most of the changes in a boy's body during puberty, and men need sperm to be able to reproduce (be the father of a baby).
In girls, these hormones target the two ovaries, which contain eggs that have been in the girl's body since she was born. The hormones cause the ovaries to start making another hormone, called estrogen. Together, these hormones prepare a girl's body to start her periods and be able to become pregnant someday.
Boys and girls both begin to grow hair under their arms and their pubic areas (on and around the genitals). It starts out looking light and thin. Then, as kids go through puberty, it becomes longer, thicker, heavier, curlier, and darker. Eventually, boys also start to grow hair on their faces
When you go through puberty, it might seem like your sleeves are always getting shorter and your pants are creeping up your legs. That's because you're having a growth spurt that lasts for about 2 to 3 years. When that growth spurt is at its peak, some kids grow 4 or more inches (10 or more centimeters) in a year! At the end of your growth spurt, you'll have reached your adult height — or just about.
But your height isn't the only thing that changes during puberty.
With all this quick growth, it can seem like one part of your body — your feet, for instance — are growing faster than everything else. This can make you feel clumsy or awkward. This is normal, too! The rest of your body will eventually fill out and shape up, and you'll feel less klutzy
Your body also fills out and changes shape during puberty. A boy's shoulders will grow wider and his body will become more muscular. He may notice a bit of breast growth on his chest. Don't worry, this is normal — and it goes away for most boys by the end of puberty.
In addition, boys' voices crack and eventually become deeper, their penises grow longer and wider, and their testes get bigger. All of these changes mean that their bodies are developing as they should during puberty.
Girls' bodies usually become curvier. Their hips get wider and their breasts develop, starting with just a little swelling under the nipples. Sometimes one breast grows more quickly than the other, but most of the time they even out. Girls may start wearing bras around this time, especially if they are involved in sports or exercise classes.
One question a girl will have is: When will I get my first period? This usually happens about 2 years after her breasts start to develop. The menstrual period, or monthly cycle, is when blood is released through the vagina. That may sound alarming, but it's normal and it signals that a girl is growing up and her body is preparing so that she can have a baby someday.
Attention: NOTHING on this site may be reproduced in any fashion whatsoever without explicit consent (in writing) of the owner of said material, unless otherwise stated on the page where the content originated. Search engines are free to index and cache our content. Users who post their account names or personal information in their questions have no expectation of privacy beyond that point for anything they disclose. Questions are otherwise considered anonymous to the general public.