The World Health Organization has highlighted growing evidence that tobacco smoking can affect reproductive health and may make it more difficult for people to conceive.

According to a new WHO knowledge summary, tobacco use has been linked to infertility among women, problems affecting sperm and sexual function among men, and poorer outcomes for some people undergoing fertility treatment. The organization also cautioned that exposure to second-hand smoke may carry reproductive risks, meaning that people who do not smoke themselves can also be affected.

Infertility is a significant global health concern. WHO estimates that around one in six people of reproductive age experience infertility at some point in their lives. The organization defines infertility as being unable to achieve pregnancy after at least 12 months of regular unprotected sexual intercourse.

Smoking and Female Fertility

Evidence summarized by WHO indicates a substantial association between current tobacco smoking and infertility in women. A systematic review covering studies conducted from 2000 through 2026 found that women who currently smoke had a higher risk of infertility than women who do not smoke.

The findings also suggest that stopping smoking may reduce some of the reproductive risks associated with continued tobacco exposure. WHO therefore emphasizes quitting tobacco as an important step for people who are planning to have children.

Effects on Male Reproductive Health

The health impact of tobacco is not limited to women. WHO also points to research involving more than 60,000 men, which associated smoking with several forms of reproductive dysfunction.

These problems included abnormalities in semen, reduced sperm movement, abnormal sperm shape and sexual difficulties. Such changes can potentially interfere with the ability to conceive.

Fertility Treatment May Also Be Affected

Smoking may also influence the effectiveness of assisted reproductive procedures. WHO cites research examining fertility treatment outcomes in which cigarette smoking was associated with fewer pregnancies and live births following assisted reproduction, including in-vitro fertilization.

This adds another concern for people who are already seeking medical assistance to overcome infertility.

Second-Hand Smoke Is Also a Concern

WHO has warned that reproductive health risks are not necessarily limited to people who actively smoke. Exposure to tobacco smoke from other people may also affect fertility.

The organization says women exposed to second-hand smoke may face a higher risk of infertility and potentially lower chances of becoming pregnant during individual attempts to conceive.

WHO Calls for Greater Awareness

WHO recommends that healthcare professionals discuss the reproductive effects of tobacco with individuals and couples who are planning a pregnancy. It also encourages healthcare providers to offer evidence-based assistance to people who want to quit smoking.

While the strongest evidence currently concerns conventional cigarette smoking, WHO says research into products such as electronic cigarettes, waterpipes and smokeless tobacco is continuing.

The latest WHO publication adds fertility to the long list of health concerns associated with tobacco use. The organization says helping tobacco users quit can form an important part of protecting reproductive health as well as preventing other tobacco-related diseases.