Vaping continues to deliver unexpected, positive side effects. At least if you were previously a smoker. In addition to less damage to the lungs, vejpning can improve sperm quality, according to new Swiss research.
The study also links vejpanding to a reduced risk of miscarriage compared to smoking. But: no nicotine at all is still the absolute best.
Researchers at the University Hospital of Lausanne, Switzerland, examined the sperm quality of smoking men who switched to vejpning during IVF treatment. They compared 151 smokers and 145 vejp-only men who underwent IVF between May 2022 and January 2024, and the results were recently published in Scientific Reports. According to the researchers, the switch led to clear improvements in sperm motility - which is crucial for fertility - while reducing the risk of miscarriage in the partner.
"Our research shows that vejpa is much better than smoking for improving fertility. It goes without saying that no nicotine at all is the best, but this is a step in the right direction for those who otherwise cannot quit," lead researcher Dr Rita Rahban told News Medical.
Better than cigarettes - but worse than nothing at all
The study involved men who all smoked and had fertility problems. Those who switched to e-cigarettes significantly improved their sperm motility compared to those who continued to vape.
But the researchers emphasise that they do not consider vejpning to be harmless - it is just less harmful than cigarettes.
"No form of inhaled nicotine is good for the body. But vejp reduces the amount of toxins and may therefore lead to better reproductive health than smoking," says Rita Rahban.
Previous research has pointed in another direction
However, other studies have warned of negative effects on fertility even from vejpning. A Danish study from 2024, published in "Andrology", suggested that young men who vejp daily have lower sperm concentration compared to both non-vejp users and smokers. This was despite the fact that testosterone levels were normal.
Studies from the University of Southern California have also shown that certain flavours in e-liquids can damage sperm motility and integrity - even if the liquid is nicotine-free.
"The nicotine is one thing, but some of the chemicals in the flavours can have direct toxicological effects on sperm," Adam Martin, a toxicologist at USC, told The Guardian.
Black and white: smoking is the worst
What is clear, however, is that cigarettes are still the clear loser for those who want to become parents and are experiencing difficulties. The amount of carcinogens, heavy metals and other harmful substances in tobacco smoke destroys both sperm DNA and sperm motility - increasing the risk of both infertility and miscarriage.
"So compared to smoking, vejpning is definitely better for fertility," says Rita Rahban.
However, many fertility clinics are cautious about recommending vejpning as an alternative. The Copenhagen Fertility Centre warns against all types of nicotine products before IVF.
"Nicotine negatively affects the blood flow to the testicles and ovaries. So our advice is always to quit completely," doctor Mette Holm told Ekstra Bladet.
