Smoking tobacco may harm people’s chances of getting pregnant, says WHO 

Smoking tobacco is also associated with potentially lower chances of success from some fertility treatments. File photo: iStock

Smoking tobacco may have a negative impact in people’s chances of getting pregnant with harmful impacts for men and women, the World Health Organization (WHO) said on Tuesday.

It also raised the alarm about emerging evidence of potential risks to fertility linked to products such as smokeless tobacco as well as nicotine products such as vapes[/url[.

Smoking tobacco is also associated with potentially lower chances of success from some fertility treatments, the WHO said.

Around one in six people will experience infertility during their lives for a variety of reasons.

This new summary is based on a review of decades of studies from around the world.

It pointed to a systematic review of studies dating from 2000 to 2026 which showed the risk of infertility is 1.4 times higher in women who currently smoke than women who do not smoke.

However, the review also found evidence women who stop smoking tobacco may have a 25% lower risk of infertility compared with women who continue smoking.

This suggests quitting tobacco can make “a meaningful difference”, the WHO said.

The review also found studies showing an increase in infertility when women are exposed to second-hand smoke even if they do not smoke themselves.

These women may have a lower chance of conceiving each month they are trying to get pregnant.

For men, the health body said it is “challenging to conduct studies to determine whether tobacco use in men results in fewer pregnancies and live births with their female partners.” 

It identified a review of 44 studies involving more than 60,000 men which found smoking was associated with harmful effects on semen, sperm and on sexual function.

These can all lead to infertility.

“Most of the evidence indicated that more men who smoked had erectile dysfunction (also known as impotence) and ejaculation problems than men who did not,” the WHO review said.

The paper also identified a study which suggested hookah smoking may reduce sperm volume in men. Another found waterpipe smoking may be associated with lower sperm quality.

Fertility treatment 

The WHO also cautioned the chances of success from infertility treatment can be impacted.

It highlighted a review of 21 studies, saying this showed “cigarette smoking was linked to fewer live births and fewer pregnancies following assisted reproduction, like invitro fertilization”.

It added findings suggested: “The chances of successful outcomes may be roughly halved by cigarette smoking”.

The summary focuses on tobacco, but said: “Evidence is still emerging regarding use of other tobacco products, including waterpipe and smokeless tobacco, and nicotine products such as e-cigarettes.” 

It urged further research into the impacts of other nicotine products on fertility. 

So far, it said there has been “a relatively small amount of research” into the links between vaping and infertility.

However the paper refers to one American study with over 4,500 women which found that ever having vaped was associated with 20% drop in fertility.

It advised healthcare workers should tell people planning to get pregnant about all of these risks from the various products and provide supports to help them quit.

The knowledge summary “Tobacco and infertility” can be read on the WHO website from Tuesday.