Why do changes happen to boys and girls

The changes in your body during puberty are caused by hormones, which are chemicals produced in your body. These hormones are like chemical messages that cause the testicles or the ovaries to release other hormones.

There is no set age when this will happen. Puberty may start when you are eight or it may not start until much later. In people with a vagina, puberty can starts anywhere between the ages of eight and 13 years old but often the first changes happen around 10 or 11 years of age. In people with a penis, puberty tends to start a little later — somewhere between 10 and 15 years.

For many boys, the first changes start to happen when they are around 11 or 12 years old. The main hormones during puberty are testosterone for those with a penis, and oestrogen and progesterone for those with a vagina. During puberty your ovaries get bigger and your body will start to produce two hormones — oestrogen and progesterone. Oestrogen causes your breast to grow and helps your vagina, uterus and fallopian tubes to develop. It also makes you grow taller and also changes the way fat is stored on your body making your waist, hips and buttocks more obvious.

Testosterone levels rise significantly during puberty. When levels are high enough, testosterone starts the production of sperm, causes the chest and shoulders to broaden and causes facial hair to grow. In people with a vagina the breasts will grow and your vagina, uterus and fallopian tubes will develop. The influx of hormones during puberty can cause a range of feelings or emotions and these feelings can change often. You might get:. Their bodies increase in size and shape during puberty.

Their hips become more rounded and they get a more defined waist. The vulva, vagina and nipples get bigger and the breasts begin to develop, sometimes unevenly.

Other changes include pubic hair appearing and a vaginal discharge — an increase in the mucous produced in the vagina. Their shoulders and chests become broader and their muscles get bigger. They may have a temporary swelling of the breasts as their hormones sort themselves out. Their voices get deeper and may go up and down or sometimes sound quite croaky all in one sentence. The penis and testicles will get bigger; they have more erections, sometimes for no reason. Menstruation is more commonly known as a period — it is a normal and healthy part of having a uterus.

The first period usually occurs between nine and 14 years, generally when they weigh about 41 kilos and are about centimetres tall. Periods are sometimes irregular at first, but usually settle into a pattern after a few months. If you haven't started your period by the time you are 16, it would be a good idea to talk to a nurse or doctor.

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Puberty is when a child's body begins to develop and change as they become an adult. The average age for girls to begin puberty is 11, while for boys the average age is Late or early puberty Children who begin puberty either very early before the age of 8 or very late after 14 should see a doctor just to make sure they're in good health.

Read more about puberty problems. First signs of puberty in girls The first sign of puberty in girls is usually that their breasts begin to develop. Pubic hair also starts to grow, and some girls may notice more hair on their legs and arms. Later signs of puberty in girls After a year or so of puberty beginning, and for the next couple of years: girls' breasts continue to grow and become fuller around 2 years after beginning puberty, girls usually have their first period pubic hair becomes coarser and curlier underarm hair begins to grow — some girls also have hair in other parts of their body, such as their top lip, and this is completely normal girls start to sweat more girls often get acne — a skin condition that shows up as different types of spots, including whiteheads, blackheads and pus-filled spots called pustules girls have a white vaginal discharge girls go through a growth spurt — from the time their periods start, girls grow 5 to 7.

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