Smokers hoping to start a family were warned by doctors that their habit could make them infertile and cause miscarriages and birth defects.
In a report, the British Medical Association (BMA) estimated 120,000 British men aged 30 to 50 had become impotent because of smoking. Up to 5,000 miscarriages every year were linked to smoking and passive smoking, and tobacco was implicated in 1,200 cases of malignant cervical cancer each year.
Women who smoked were also less likely to become pregnant and reduced their chances of successful fertility treatment.
The BMA published the report on the 50th anniversary of official Government recognition that smoking causes cancer. But health concerns linked to reproductive problems have been less well-documented.
Dr Vivienne Nathanson, head of science and ethics at the BMA, said: “The scale of damage smoking causes to reproductive and child health is shocking. Women know they should not smoke during pregnancy, but the message needs to be far stronger. Men and women who want to have children should bin cigarettes. Men who want to continue to enjoy sex should forget about lighting up, given the strong evidence that smoking is a major cause of male sexual impotence.”