Q: I'm worried that she's too short at 145 centimetres and wonder if she should be given limb-lengthening injections before she gets her first period.

She weighs 38 kilograms. I'm 160cm tall and my husband is 170cm. - Concerned Mum

Your daughter's height and weight are in the normal range for her age and the family's genetic potential. Breast development before age eight and menstruation before age nine are considered premature. So your daughter is perfectly normal.

When girls begin menstruating, they don't stop growing immediately. They usually grow another seven or eight centimetres on average.

The main purpose of using medication, such as a gonadotropin-releasing hormone analogue, is to delay "precocious puberty" - the development of early secondary sexual characteristics.

Significant growth in height can usually be achieved if the treatment is begun early enough. It's safe even when used for a long period, and the only side effects reported have been mild.

Nevertheless, using this medication on normal girls does little to boost their height, and none at all if their bones are already well developed.

If you're still concerned about your daughter's height, I suggest you see a paediatric endocrinologist. The specialist will X-ray her hands and wrist to determine her bones' level of maturity.

It's a simple procedure and the best method to determine how much more your daughter could grow and whether treatment would have any effect.

Dr Phairuch Chaiyakul, MD, an associate professor in the Division of Paediatric Endocri-nology and Metabolism in Phramonkutklao Hospital's Department of Paediatrics.