Clinical services Health Information Puberty Puberty is the process that changes a child’s body into an adult body that is capable of sexual reproduction. Puberty is triggered by the release of hormones from a small gland in at the base of the brain. For girls puberty starts at around 10 years of age with a range of eight to 13 years being normal. For boys it is usually between 11 and 12 years, however the normal range can be from 9 to 14 years. Changes for girls: breast development hips widen and body becomes curvier grow taller hair growth – hair will start to grow in pubic area, under arms and hair on the arms and legs will darken vaginal discharge – may start having a clear or whitish discharge for the vagina periods will start pimples may appear Changes for boys: shoulders and chest becomes broader grow taller body becomes more muscular voice gets deeper penis and testicles become larger and darker in colour hair growth - hair will start to grow in pubic area, under arms, chest and back and hair on the arms and legs will darken during wet dreams or when masturbating, ejaculation may occur pimples may appear.