Babies grow and at around 12 months they become toddlers. Toddlers become children at about 3 years. Children between the ages of 10 to 15 experience massive changes in their bodies. Fast growth takes place during this period. This period is called puberty and finishes by the age of 18. Usually girls go into puberty before boys.
Sex hormones released by the ovaries and testes start off puberty. Sex hormones can cause acne (spots) and emotional changes, too. This includes boys and girls becoming more interested in each other. The period during which all the physical and emotional changes take place is called adolescence.
The changes that take place during adolescence in boys and girls are summarised in the table below:
|Development of male characteristics||Development of female characteristics|
|stronger body smell||stronger body smell|
|voice deepens 'breaks'|
|testes and penis get bigger||menstruation|
|testes start making sperm||ovaries start releasing eggs|
|pubic hair grows||pubic hair grows|
|body becomes more muscular||hips get wider|
|facial hair grows|
|body hair grows||underarm hair grows|
|broad shoulders||breasts mature|