Growing Up: Changes at Puberty

1What is puberty?

Puberty is the stage when a child's body starts to change into an adult's body and the reproductive organs begin to work. The changes are controlled by hormones, chemical messengers made in the body.

Puberty usually begins somewhere between about 9 and 14 years of age. Girls often start a year or two before boys. Everyone has their own timetable: starting early or starting late are both normal.

2Changes in both girls and boys

• A growth spurt: you grow taller quickly.
• Hair grows under the arms and around the private parts (pubic hair).
• More sweat, and a stronger body smell.
• Oilier skin, and sometimes pimples (acne).
• Stronger and quickly changing feelings.

3Changes in girls

• The breasts start to develop.
• The hips become wider and the body more rounded.
• The ovaries begin to release eggs, and menstruation (the monthly period) begins.

4Changes in boys

• The voice breaks and becomes deeper, and the Adam's apple grows bigger.
• The shoulders and chest become broader and the muscles bigger.
• Hair begins to grow on the face (a beard) and sometimes on the chest.
• The testes and penis grow, and the testes begin to make sperm. Sometimes semen comes out during sleep. This is called a wet dream. It is normal and is not an illness.

5Menstruation: a normal monthly event

Each month, the lining of the uterus becomes thick and soft, ready in case a baby starts to grow. When there is no baby, the lining is not needed. It breaks down and flows out of the vagina as blood over about 3 to 7 days. This is the menstrual period. A girl's first period is a sign that her puberty has begun.

Periods usually come about once every 28 days, but in the first years they may not be regular. A period is not a sickness and it is not dirty. Girls can go to school, study and play as usual. Mild pain in the lower belly is common; if the pain is very bad, tell a parent, a teacher or a nurse.

6Feelings change too

During puberty, you may feel happy one minute and sad or angry the next, want more privacy, and care more about how you look. This is normal. Talk to a parent, guardian, teacher or other trusted adult about your questions. Never tease anyone about their body; everyone is going through the same journey.

Try it yourself

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