Risks slashed if pregnant women quit smoking before 15 weeks
By Lilian Anekwe
Pregnant women who quit smoking before 15 weeks dramatically reduce their risk of complications, a new study shows.
Women who stopped before week 15 lowered their risk of having an underweight baby or going into spontaneous premature labour to the same level as non-smokers.
The New Zealand researchers said their study suggested interventions to stop smoking were needed right at the start of pregnancy – and suggested GPs could use the 15-week deadline to motivate women to quit.
The study of 2,500 women, published by the BMJ last week, found women who continued to smoke after week 15 had a 3.2-fold increased risk of giving birth prematurely compared with those who had stopped.
Women who failed to quit also had almost a doubled risk of having small babies, although there was no difference in rates of spontaneous preterm birth and babies small for gestational between the groups.
Study leader Dr Lesley McCowan, associate professor of obstetrics and gynaecology at the University of Auckland, said the results were of ‘considerable public health importance'.
‘The adverse effects of smoking on late pregnancy outcomes may be largely reversible if smoking is stopped early in pregnancy. Maternity care providers should emphasise the major health benefits if women cease to smoke before 15 weeks' gestation.'
Dr Tim Coleman, a GP in Nottingham and who has done research on smoking cessation, said: ‘The authors speculate there might be a critical window before which it's more beneficial to stop. But my message would be that although the earlier women quit the better, GPs should still stress the importance of quitting even in women in late pregnancy.'