Switching From Smoking to Vaping Improves Sperm Quality and Reduces the Chance of Miscarriages

Switching from combustible cigarettes to vaping continues to look like a net win for adult smokers, even when the focus narrows to the sensitive growing issue of fertility. New human data show measurable benefits for would‑be fathers who vape rather than smoke, putting an emphasis on the fact that vapes should be considered as a harm‑reduction tool—not a health supplement. And parallel research on women and on several long‑term markers support these findings. Taken together, the studies reviewed below reinforce a familiar message: while the safest destination remains life without a nicotine addiction, abandoning smoke is the priority.

Smoke versus vapour for fertility

The clearest head‑to‑head evidence so far comes from a recent Scientific Reports paper that analysed 296 heterosexual couples undergoing IVF between May 2022 and January 2024. All female partners were non‑smokers. Men who had vaped exclusively for at least six months produced sperm with slightly better forward motility (≈49 %) than cigarette smokers (≈48 %) and showed lower blood prolactin, a hormone sometimes linked to sub‑fertility. Those modest laboratory differences translated into meaningful clinical gains: miscarriage after ultrasound confirmation fell from 36 % in the smoking group to 12 % in the vaping group, while live‑birth success jumped from 41 % to 56 %. Once hormonal markers such as FSH and embryo quality were added to the statistical model, nicotine source itself lost independent significance, yet the overall pattern still favoured vapour over smoke.

A separate University College London project examined blood samples from more than 8,000 women and found that regular vapers had lower anti‑Müllerian hormone (AMH) levels, a rough gauge of ovarian reserve. Media headlines quickly warned would‑be mothers to ditch their devices. Yet AMH is an indirect marker; it does not capture egg quality or predict how fast reserves decline. Importantly, the National Health Service still advises pregnant smokers to consider switching to vaping if they cannot quit nicotine altogether, because vapour delivers far fewer toxicants than smoke.

The World Health Organization’s 2024 HBSC survey of 280,000 pupils across 44 countries revealed that UK girls aged 15 are more likely than boys to have tried vaping, smoking or alcoho. Researchers called the pattern “concerning,” but did note that vaping appears to be replacing smoking in that age group. From a harm‑reduction standpoint, displacement of cigarettes by e‑cigarettes is a step forward, even if not ideal. THR advocates also highlight underlying drivers—stress, weight control, social pressure—that require broader public‑health interventions, not just product bans.

Clearing the haze

Laboratory studies often generate alarming headlines. A Turkish experiment exposed rats to cigarette smoke, e‑cigarette vapour or clean air; both exposure groups showed oxidative stress and marginal sperm‑count reductions. Experts note that rodent chambers do not replicate human usage patterns, nicotine doses or device designs, so direct translation to people is unreliable. As Australian tobacco‑treatment specialist Colin Mendelsohn observed at the time, human studies, not animal proxies, must guide fertility counselling.

One cross‑sectional U.S. survey linked daily e‑cigarette use to higher odds of erectile dysfunction even after adjusting for age and heart disease. However, smoking history was poorly controlled, and paradoxically, current smokers in the same dataset showed no extra risk, undermining firm conclusions. More persuasive are vascular findings: chronic vapers had impaired endothelial function, but the damage was similar to or slightly less than that seen in smokers, and far worse in dual users.

So again, while quitting nicotine entirely is the recomended path; switching to vaping is a harm‑reduction step. Men undergoing IVF who can’t quit nicotine should know that vaping improves sperm motility and reduces miscarriage risk compared to smoking. Similarly, while starting vaping is not recommended for non-smokers, for women trying to conceive switching from cigarettes to vaping is a safer choice.

The broader harm‑reduction picture

Tobacco harm reduction is about relative risk. The studies above confirm that moving from combustion to vapour reduces specific reproductive hazards. For policymakers, this evidence argues against blanket vape bans that could push adults back to cigarettes. For healthcare providers, it underscores the importance of nuanced counselling: vaping can be a useful bridge away from smoking, especially to adolescents and prospective parents.

As research evolves, so must guidance. Future trials that include non‑nicotine controls, device‑specific toxicology and long‑term offspring outcomes would help refine the advice. Until then, the hierarchy remains clear: no nicotine > vaping > smoking. For couples investing emotionally and financially in fertility treatment, that simple ranking can inform choices today.

Sperm Count is 50% Lower in Males With Smoking Fathers