Babies whose teenage mothers smoked during pregnancy are more likely to suffer from low birthweight (LBW) than babies whose mothers did not smoke, according to a study in the latest Medical Journal of Australia.

Associate Professor Elizabeth Sullivan and Denise Chan from the University of New South Wales studied the association between smoking in pregnant teenagers and baby birthweight.

They found that although smoking throughout pregnancy increased the risk of LBW, the babies of mothers who stopped smoking before 20 weeks’ gestation had birthweights similar to babies born to non-smokers.

LBW is a key indicator of a newborn’s overall health but also affects childhood development and predisposes children to chronic disease later in life.

Reducing the quantity of cigarettes smoked during pregnancy also has an impact on the risk of LBW in infants.

"Our results suggest that there is further scope to reduce smoking in pregnancy in teenage mothers," the authors say.

"The quitting rate of only one in 15 among teenage mothers during pregnancy indicates how difficult smoking cessation remains for pregnant women.

"Harm minimisation strategies need to continue to target smoking cessation in mothers, with health care providers, including general practitioners, in an ideal position to influence maternal smoking rates.

"The important clinical and public health message from our study is that quitting smoking before the second half of pregnancy has a positive impact on birthweight."

The Medical Journal of Australia is a publication of the Australian Medical Association.

(Source: Medical Journal of Australia: Australian Medical Association: April 2008)