WHO Links Smoking to Higher Infertility Risk
The World Health Organization says that tobacco use is strongly associated with difficulty conceiving, putting women who smoke at a 40 percent higher risk of infertility than those who do not, and urging anyone planning a pregnancy to quit.
Dr Kerstin Schotte of WHO’s Tobacco Free Initiative said the message for people who want children is to stop smoking in order to improve general and reproductive health. The agency defines infertility as no pregnancy after twelve months or more of regular unprotected intercourse, a condition it says affects one in six people worldwide. A new evidence summary finds decades of research tying smoking to infertility in women and to poorer sperm quality and sexual function in men. Second-hand smoke can also raise risk for non-smokers. Women who have quit appear to face about 25 percent lower infertility risk than those who still smoke.
Infertility is not only a female diagnosis. A review of 44 studies covering more than 60,000 men linked smoking to semen abnormalities and sexual dysfunction, including erectile and ejaculation problems, absence of sperm, weak motility and abnormal shape. Smoking also appears to blunt assisted reproduction. Twenty-one earlier studies associated cigarettes with fewer pregnancies and live births after treatments such as IVF, with success rates in some analyses roughly halved.
Evidence on waterpipes, e-cigarettes, smokeless tobacco and other nicotine products is thinner. WHO said on Tuesday that those products may carry reproductive risks and need more study, and that hookah use may affect male fertility. Second-hand exposure may also lower a woman’s chance of conceiving in any given month. The agency has asked clinicians to raise the subject with couples planning a pregnancy and to offer brief, evidence-based quit advice in ordinary health settings.
The report does not claim that every smoker will be infertile or that quitting instantly restores fertility. It does say the association is consistent enough that tobacco should sit in the same conversation as age, infection and other known factors when people try to have a child.
