Obstetrics

December 03, 2004

Babies smaller at birth tend to be more prone to diseases later in life, and may suffer developmental delays. So although the original study found no evidence of actual damage, it raised concerns.

In The Lancet John Newnham, of King Edward Memorial Hospital in Subiaco, Australia, and colleagues put these fears to rest after following the same group of children and examining them at 1, 2, 3, 5 and 8 years of age.

They found that by the age of one all the small babies had caught up in growth and had developed normally, with no effects on language, behaviour or brain development.

“Exposure to multiple prenatal ultrasound examinations from 18 weeks’ gestation onwards might be associated with a small effect on foetal growth but is followed in childhood by growth and measures of developmental outcome similar to children who had received a single prenatal scan,” the team concludes.

They studied the progress of about 2,700 children, half of whom had been exposed to repeated ultrasounds before birth. None had any congenital abnormalities.

“Our results also provide reassurance that multiple prenatal ultrasound scans are not followed by smaller body size in infancy or childhood,” Professor Newnham added.

Ultrasound is a valuable technique in pregnancy, reassuring mothers and providing early evidence of foetal abnormalities. Having as many as five scans would be rare, but the removal of fears that they might cause damage is an important step.

But Professor Newnham and his colleagues said that more research was needed. “In view of the widespread and liberal use of this technology, we are responsible for ensuring the safety of its use,” they said.

Copyright 2004 Times Newspapers Ltd.