Is your child a late bloomer?

In lower secondary school, Ivan was so small that his classmates called him 'shrimp'. He shrugged off their name-calling but deep down, it hurt.

Concerned about his stature, his mother took him to their family doctor, who referred Ivan to a paediatric endocrinologist, a doctor specialising in hormone disorders in children.

Cheryl was self-conscious about her flat chest when she was in Secondary 2. All the other girls in her class were wearing bras. When she showed no signs of menstruation by Secondary 4, she too went to a specialist.

Fortunately for Ivan, his was just a case of delayed puberty. Associate Professor Loke Kah Yin from the National University Hospital assured him that he was normal.

Boys normally start puberty between the ages of 91/2 and 14, and girls between nine and 131/2. Delayed puberty is when there are no signs of any body changes for boys by 14 years and for girls, by 13.

Recent media reports about a girl who got pregnant at age nine raised questions about when the transition to adulthood starts in children.

According to Prof Loke, delayed puberty is more commonly seen in boys than in girls, whereas precocious puberty (early puberty) happens more frequently in girls. This is because boys mature later and girls, earlier. And while obese children are more prone to precocious puberty, delayed puberty is more likely to occur in underweight children.

'In most instances, children with delayed puberty have parents who were themselves late developers,' said Prof Loke. 'It can be hard on these kids because their friends can be cruel and call them names. And this affects their self-esteem and confidence.'

There are several reasons why puberty may be delayed. Most often, it is simply a pattern of growth and development in the family. One or both of the child's parents probably reached puberty later than usual.

This is called constitutional delay or - simply put - a late bloomer. It does not need treatment, only reassurance from the doctor that the child will eventually catch up.

When Ivan hit puberty two years later, he even overtook a few of his classmates who had earlier teased him.

Hormonal problems
In some children, the 'switch' in the brain which releases the hormones that bring on puberty comes on later than normal. There are also those who are born with the inability to produce these hormones. The cause is sometimes a tumour in the brain.

Or it may be due to malnutrition. Children who are underweight or small-framed are more susceptible to delayed puberty. For example, ballerinas and athletes may be late developers because their level of exercise keeps them lean, with a low body mass index.

Problems with the chromosomes can also interfere with normal growth processes. Cheryl was found to be suffering from Turner syndrome, which occurs when one of the female's two X chromosomes is abnormal or missing.

This causes problems with growth and the development of the ovaries and production of sex hormones. Women who have untreated Turner syndrome tend to be shorter than normal, are infertile, and may have other medical problems.

Males with Klinefelter syndrome are born with an extra X chromosome (XXY instead of XY). This condition can also affect sexual development.

Mumps, an infection of the salivary glands, may cause inflammation of the testes. This condition, known as orchitis, can affect the production of testosterone (male sex hormone) which affects puberty.

Treatment
The doctor will conduct a physical exam and check out the family history. He may order blood tests to check for thyroid, pituitary, chromosomal, or other problems. He may also do a "bone age" X-ray, to see if the child's bones are maturing normally.

In some cases, injections of androgen (male sex hormones) for boys and oestrogen (female sex hormones) for girls are given monthly to get puberty going. Each injection of androgen costs about $30, and the oestrogen tablets cost about $20 per month.

When the underlying cause is treated, puberty is likely to proceed normally.

The following are the most common symptoms of delayed puberty:

GIRLS

>>lack of breast development by age 13
>>more than five years between breast growth and menstrual period
>>lack of pubic hair by age14
>>Failure to menstruate by age 16

BOYS
>>Lack of testicular enlargement by age 14
>>Lack of pubic hair by age15
>>More than five years to complete genital enlargement

Long and short of growth spurts

Boys have a greater growth rate than girls during the growth spurt. Over all, girls end up about 10per cent shorter than boys.

'But there are more boys seeking medical treatment for being short because society expects them to be tall,' said paediatric endocrinologist Loke Kah Yin of the National University Hospital.

Associate Professor Loke explained that short stature in children is often due to hereditary factors or delayed puberty. If parents are short, chances are, the child will take after them. If one parent is short and the other tall, the child's height may be somewhere in between, or he may take after either one of them.

During their growth spurt, boys are known to suddenly shoot up, with their height increasing between 28cm and 30cm. In the case of girls, once they start menstruating, their days of growth are almost over. They are likely to grow another 5cm or so, and then stop.

In terms of weight gain, girls who are plump will find themselves losing their puppy fat, Instead, they begin to fill up in other places - breasts and hips. It is common for girls to put on 18kg to 20kg during puberty.

With the boys, testosterone increases their lean body mass. They begin to lose their body fat and develop muscle instead. As a whole, boys can expect to put on between 25kg and 30kg during this period.