Almost half of children whose mothers smoke have asked them to quit, a survey has found.
Smoking increases women's risk of cervical cancer and osteoporosis
The poll of 500 smoking mothers also found two-thirds felt guilty about spending money on cigarettes which could be used for their children.
And almost all the women said they were concerned about the effect their smoking habit may have on the health of their child.
The survey by website tickbox.net was launched to mark No Smoking Day.
It was commissioned by the pharmaceutical company Pfizer.
Nearly a quarter of women in the UK are believed to be smokers, and around 41,000 women are estimated to die prematurely each year because of the effects of smoking.
The proportion of women smokers is highest in 20-24 year olds, with 30% of women in that age range smoking.
As well as the risks to heart and lung health that male smokers face, women who smoke are also at increased risk of cancer of the cervix, a range of problems relating to reproductive health, and osteoporosis.
Ruth Bosworth, of Quit, an independent stop smoking charity, said: "This research demonstrates that women are unintentionally putting their nicotine addiction ahead of the health of their children.
"Smokers are sacrificing their own health and, in the case of mums, the health of their children as well."
But Simon Clark of the smokers' rights group Forest said: "I don't think parents should give in to emotional blackmail.
"There are so many things in life that carry a health risk; drinking too much or eating the wrong food. Smoking comes under that category."
Twenty per cent of smokers are set to try to give up their habit when England's ban on smoking in enclosed public spaces comes into force on July 1, a YouGov poll of 2,200 adults published on Wednesday found.
If all were successful, around 1.25 million premature deaths could be prevented, say the organisers of No Smoking Day, as one in two smokers die early.
A range of measures, including NHS stop smoking services and nicotine replacement therapy, are available to those who want to quit.
In addition, researchers at Exeter University say short bouts of exercise can help people resist the temptation to have a cigarette.
'Smokers should seek help'
Dr Vivienne Nathanson, head of science and ethics at the British Medical Association, said smokers should use the forthcoming ban as an incentive to quit.
"Given they will not be able to smoke in virtually all public indoor premises it makes sense to take this a step further and stop all together.
"Around half of all smokers will die because of their habit. For this reason, as doctors, we are urging smokers to seek help to quit."
Deborah Arnott, director of Action on Smoking and Health, said figures published earlier this week by the Conservatives showing local health bodies were cutting spending on services helping people to stop were worrying, as the experience in Scotland showed a ban was an incentive for many to quit.
"We urge primary care trusts to urgently review their budgets for the coming year and to step up provision of cessation services wherever possible."
Keith Prowse, chairman of the British Lung Foundation, added: "If we truly want to protect people's health we have to make sure that effective services are in place to help them give up."