by Dr Vera Oh. Paediatrician – Sub-Specialty in Growth and Endocrinology
When does normal puberty start?
Puberty in girls can begin anytime between 8-13 years of age. In boys, it occurs later and usually begins between 9-14 years of age.
How do I know my daughter is going into puberty?
The first sign of puberty in a girl is breast enlargement. This is soon followed by a growth spurt where the child grows at a faster rate (about 6-11 cm/year). Other signs that puberty is progressing include growth of hair over the pubic region and underarm area. Her first menstrual period will usually occur about 2 years from the onset of puberty. You may also notice acne and body odour. Generally, girls gain another 5-6 cm after their first menstrual period before they stop growing completely. The pace and rate of puberty varies from child to child and depends more on the skeletal maturity of the body than on the chronological age.
What are the signs of puberty in a boy?
Boys begin with an increase in the size of their testes. This is followed by darkening of the skin over the scrotum and an increase in penile length. Growth of pubic and underarm hair follow. Other signs include acne, deepening of the voice, increase in muscle mass, erections and ejaculations. The growth spurt in boys occurs 2 years later than in girls, at about the midpoint of puberty. During this time, they can grow 7-12 cm/year for about 2 years. Boys finish growing at 17-18years of age but growth over the last few years is considerably slower.
What causes the onset of normal puberty?
Normal puberty occurs when the body reaches a certain degree of maturity and the master gland in the brain, the pituitary gland, awakens. It produces follicular stimulating hormone (FSH) and luteinizing hormone (LH), also known as gonadotrophins. These trigger a cascade of hormonal changes in the body and result in the physical signs of puberty.
When is puberty too early?
A girl who has breast development or any other signs of puberty before the age of 8 years should be assessed. In boys, signs of puberty before 9 years of age are also reasons for concern.
What causes early puberty?
Normal puberty begins when the body reaches a certain degree of maturity and activates the master gland (the pituitary gland). The hormones (gonadotrophins) produced by this gland stimulate the ovaries in girls and testes in boys to grow and produce their respective hormones. Estrogens from ovaries bring about changes in the breast. Testosterone from the testes causes the changes in body hair and voice. These sex hormones lead to an increase in the growth rate (growth spurt).
Signs of puberty can be caused by external sources of sex hormones. Puberty that occurs earlier than usual is known as precocious puberty. Precocious puberty can sometimes originate in the pituitary gland. This is known as gonadotrophin-dependent or central precocious puberty. Infections, developmental abnormalities or injury in the area of the gland can lead to this problem. Often, especially in girls, no cause is found and they are completely healthy. This is known as idiopathic central precocious puberty.
Gonadotrophin-independent precocious puberty or peripheral precocious puberty is due to independent sources of sex hormones from the ovaries, testes or adrenal glands. Ovarian cysts, tumours in the ovaries / testes/ adrenals or congenital adrenal hyperplasia are some causes.
What can we expect at the doctor’s visit?
The doctor will examine the child to assess the degree of maturity and extent of pubertal development. This will include a breast examination and an inspection of the private parts.
Depending on the physical finding, the doctor may recommend tests like a bone age assessment. An ultrasound of the internal organs may also be suggested. Sometimes, a stimulation test is required. During a stimulation test, the child is given medication and a series of blood tests are done to monitor the body’s response to the drug given. This gives us an idea of whether the child is in true puberty or not.
Is there any treatment for early puberty?
In gonadotrophin-independent puberty, the underlying cause has to be addressed. With idiopathic central precocious puberty, a monthly or 3 monthly injection can be used to retard the progress of puberty. This form of treatment should be supervised by a paediatrician experienced in its use.