The risk of giving birth to premature or small babies can be cut if expectant mothers quit smoking within the first 15 weeks of pregnancy, according to research.
A study published in the British Medical Journal (BMJ) says that kicking the habit reduces the risks to those of a non-smoker.
Says Dr Lesley McCowan, associate professor of obstetrics and gynaecology at the University of Auckland: `In women who stopped smoking, rates of spontaneous pre-term birth and small-for-gestational-age infants did not differ from those in non-smokers, indicating that these severe adverse effects of smoking may be reversible.`
The trial of 2,500 pregnant women was divided into three groups: non-smokers, who represented 80% (1,992) of the total, stopped smokers 10% and current smokers 10%.
No difference in baby size and rates of premature births were found between stopped smokers and non-smokers, but there were much higher levels among current smokers.