Small for gestational age

If a child is born small for gestational age (meaning smaller than average in length and/or weight for a certain week of pregnancy) they may remain relatively small at a later age and even as an adult person.

The causes behind an infant being born SGA are quite complex, and may include:

  • Factors associated with the mother’s age
  • Any infections contracted during pregnancy
  • Alcohol intake
  • Cigarette smoking

Other possible causes linked to SGA are a lack of oxygen reaching the unborn child through the blood supply from the placenta, or an inherited condition that affects the unborn child’s growth. However, in around half of all cases, doctors cannot find any particular reason why a child is born SGA.

How will this condition affect a child’s height?

While 90% of infants born SGA grow fast enough to catch up with other children of their age, the remaining 10% of children born SGA are still small for their age by age 2. For these children, the risk of having short height when they reach adulthood is 5–7 times greater than for the normal child.

How is SGA diagnosed?

Doctors will firstly look for all the possible factors that can cause a child to be born too small, some of which have already been described above. A child may be referred to a specialist who will look for any genetic disorders that could be behind the slower growth. SGA children are also often seen by a paediatric endocrinologist, who is a doctor specialising in treating children with an imbalance in the hormones affecting growth and development.

The importance of early diagnosis

For a child born SGA, the earlier the diagnosis, the better the prospects for treatment. The benefits of growth hormone treatment are greater when children begin therapy in early childhood. In other words, the earlier a child begins growth hormone therapy, the more likely they are to achieve an adult height comparable to that of the average person.

Growth hormone treatment in SGA children

Once SGA has been diagnosed, growth hormone injections can help a child’s growth catch up to normal height during early childhood. When growth hormone treatment is continued after this period, it helps to maintain normal growth later in childhood, with the aim of children eventually reaching an adult height within the normal range.

The response to growth hormone treatment varies from one individual to another, but most children treated over several years will reach normal or near normal adult height.

Growth hormone injections are normally given once-daily in the evening. When the child is very young, parents are trained to give these injections. Later on, children can inject themselves when they feel confident enough. Devices are now available that make injecting growth hormone much simpler, more comfortable and less painful. This has been achieved through advances in design such as automated needle insertion and the use of very fine needles. There is a wide choice of devices available, and whilst some require mixing before use and refrigeration once opened, others do not.

To help the doctor select an injection device that matches your requirements, it may help to read the page discussing the features of the various devices.

Meeting the challenge of growth problems

If a child doesn’t grow as fast as other children, this can have an impact on the whole family. Many children who are shorter than their schoolmates may experience emotional problems, bullying and difficulties with daily activities such as sports. For these reasons, it’s important to explain to a child that things will improve once the growth hormone treatment has been working for a while. In the meantime, remember to act towards a child according to the age they actually are, not the age they look.

It is important to continue growth hormone treatment until a child develops muscle and bone mass normally. While they are growing, it is also important to make sure that a child has a normal appetite and food intake. These positive measures should help give a child the ability and confidence to take part in activities that other children their age enjoy.

APROM ID# 1503. December 2009.