When you are trying to conceive, it is natural to focus on timing, hormones, and treatment options. Lifestyle is sometimes treated as a secondary concern. The evidence, however, places smoking among the strongest modifiable risk factors influencing reproductive health in both women and men.
The link between smoking and fertility is often misunderstood. Many people assume the impact is small, that occasional smoking is harmless, or that assisted reproductive technologies such as IVF can compensate for the effects. Research from major reproductive health organisations tells a different story.
Quick answer: Smoking is one of the most significant modifiable risk factors for fertility. It harms egg and sperm quality, disrupts hormones, reduces implantation, and lowers IVF success. The encouraging news is that the body recovers steadily after quitting, with measurable improvements often appearing within just a few months.
Lifestyle matters for fertility. A BMC Public Health study found that women with 4–5 healthy habits had a 59% lower risk of infertility.
Fill out the questionnaire, and get a personalised, holistic and evidence-based programme tailored to you.
takes 3 minutes to completeCigarette smoke contains more than 7,000 chemicals, including nicotine, carbon monoxide, polycyclic aromatic hydrocarbons, and heavy metals. Many of these compounds are reproductive toxins. They reach the ovaries, the testes, and the developing embryo through the bloodstream, often within minutes of inhalation.
Major reproductive health bodies, including the American Society for Reproductive Medicine (ASRM) and the European Society of Human Reproduction and Embryology (ESHRE), consistently conclude that smoking affects every stage of reproduction. The harm is biological rather than behavioural, which is why willpower alone is rarely enough to shift outcomes.
The reproductive processes most clearly influenced include:
Smoking sits in a category of its own among the lifestyle factors that influence fertility, because the dose-response relationship is unusually well established (ASRM, 2018).
Women are born with a finite number of eggs. Smoking accelerates the natural loss of these eggs and damages the quality of those that remain. Toxins such as polycyclic aromatic hydrocarbons can trigger cell death in ovarian follicles, effectively shortening the reproductive lifespan.
Research consistently links smoking to reduced ovarian reserve, increased follicular loss, and earlier menopause, on average between one and four years sooner than in non-smokers (ESHRE, 2021). For women planning to conceive in their thirties or forties, this acceleration matters.
Smoking also disrupts hormonal balance, particularly oestrogen production. The result is often irregular ovulation, altered menstrual cycles, and a reduced chance of conception in any given cycle.
Even when fertilisation occurs, smoking can interfere with implantation. Reduced blood flow to the uterus, changes in endometrial receptivity, and increased inflammation make it harder for an embryo to attach and develop. Clinically, this translates into longer time to pregnancy, higher miscarriage rates, and a greater risk of ectopic pregnancy. ASRM data suggest that smokers may face up to a 60 percent higher risk of infertility than non-smokers (ASRM, 2018).
This content is for educational purposes only. It has been reviewed for scientific accuracy, but it does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding medical questions or fertility treatment decisions.
Reviewed for scientific accuracy by: Dr. Mona Bungum
Last reviewed: May 2026
Lifestyle matters for fertility. A BMC Public Health study found that women with 4–5 healthy habits had a 59% lower risk of infertility.
Fill out the questionnaire, and get a personalised, holistic and evidence-based programme tailored to you.
takes 3 minutes to completeMale factors contribute to up to half of all cases of infertility. Smoking influences several of the most important sperm parameters, including concentration, motility, morphology, and DNA integrity.
One of the central mechanisms is oxidative stress. Free radicals from cigarette smoke damage the genetic material inside sperm cells, a process known as DNA fragmentation. Higher levels of fragmentation are associated with poorer fertilisation rates, lower embryo quality, and a greater risk of miscarriage (ESHRE, 2021).
Even when fertilisation succeeds, sperm DNA damage can affect early embryo development and implantation. Some studies also suggest that paternal smoking may contribute to genetic and epigenetic changes that influence offspring health later in life.
Encouragingly, sperm regenerate roughly every 64 to 72 days. Quitting several months before trying to conceive can therefore produce measurable improvements in sperm health.
When both partners smoke, the effects are not simply additive. They tend to compound.
Studies show significantly longer time to pregnancy, higher rates of infertility, and lower success rates with treatment in couples where both partners smoke. Even passive smoking, often described as second-hand smoke, has been associated with reduced fertility in non-smoking partners.
Because fertility is a shared process, addressing smoking together tends to produce better outcomes than working on it individually. The shared lifestyle change also tends to support adherence over the longer term.
A common assumption is that assisted reproductive technologies can override the effects of lifestyle. The evidence does not support this. Smoking continues to influence outcomes even in advanced treatment cycles, which is why most clinics raise the topic during planning.
Compared with non-smokers, women who smoke during IVF often experience reduced ovarian response to stimulation, fewer eggs retrieved, and a need for higher medication doses. Embryo quality and implantation rates are also affected, and pregnancy and live birth rates can be up to 30 percent lower than in non-smokers (ASRM, 2018).
Even after a positive pregnancy test, smoking continues to raise the risk of miscarriage, likely due to a combination of embryo quality and uterine environment.
For these reasons, many fertility clinics now strongly advise smoking cessation before treatment, integrate lifestyle counselling into care, and in some cases delay cycles until cessation is established. ESHRE guidelines emphasise that optimising lifestyle factors is a key part of improving outcomes from assisted reproduction.
Smoking does not stop affecting outcomes once pregnancy is achieved. During pregnancy, smoking is associated with placental complications, preterm birth, low birth weight, and an increased risk of miscarriage.
Babies exposed to smoking in utero face higher risks of growth restriction, respiratory problems, sudden infant death syndrome, and certain neurodevelopmental challenges. These risks are well documented across public health authorities, including Sundhedsstyrelsen and international bodies.
Emerging research also points to intergenerational effects. Sons of women who smoked during pregnancy may show reduced sperm quality decades later, and some studies link prenatal smoke exposure to a higher risk of chronic disease in adulthood. Fertility, in this sense, is not only about achieving pregnancy. It is about long-term health for the next generation.
When it comes to smoking and fertility, the message across the major reproductive health bodies, including ASRM, ESHRE, and Sundhedsstyrelsen, is consistent.
There is no safe level of smoking when trying to conceive. Even low daily intake has been associated with measurable harm.
Stopping before pregnancy significantly improves fertility outcomes, IVF success, and pregnancy health. Earlier is better, although stopping at any point before or during treatment is helpful.
Both partners should stop, since fertility is a shared process and passive exposure also affects outcomes.
Structured cessation support, including counselling, behavioural therapy, and where appropriate nicotine replacement therapy, increases the likelihood of long-term success. Sundhedsstyrelsen emphasises that combined support is more effective than willpower alone.
The body begins to recover soon after the last cigarette. The timeline is gradual but predictable:
These changes do not require perfection. Even partial reduction is associated with some benefit, although complete cessation produces the strongest improvements. Stopping shortly before IVF can still make a difference, although planning ahead allows the full benefit of recovery to take hold.
If you or your partner smoke, the following steps tend to be the most effective in practice:
Quitting in the middle of a fertility journey is rarely easy, particularly when stress is already high. The benefit, though, is rarely in doubt. Smoking is one of the few areas of fertility where the mechanism is well understood, the impact is significant, and the intervention works. These steps form part of preparing your body for pregnancy in a way that supports both partners through the journey ahead.
For couples navigating fertility decisions, the volume of information available can feel overwhelming. Conceivio is designed to make that process clearer and more grounded.
Conceivio supports women and couples by:
The aim is to help you make confident, informed decisions about your fertility, including the lifestyle changes that have the greatest impact on outcomes.
These are some of the most common questions people search for when considering the link between smoking and fertility. The answers below are based on guidance from leading reproductive health organisations.
Yes. Smoking accelerates the loss of eggs, reduces ovarian reserve, disrupts hormones, and lowers the chance of implantation. Women who smoke also tend to reach menopause earlier than non-smokers, often by one to four years.
Smoking lowers sperm count, reduces motility, increases the proportion of abnormally shaped sperm, and damages sperm DNA. The damage is largely caused by oxidative stress, and improvements typically appear within three to four months of quitting.
Not fully. IVF success rates are lower in smokers, with some studies reporting up to 30 percent lower pregnancy rates. Quitting before treatment improves egg yield, embryo quality, implantation, and live birth outcomes.
Ideally three months or more. This allows new sperm to develop, supports a healthier ovarian environment, and gives the body time to recover. Stopping at any point before or during a fertility journey is still associated with benefit.
Yes. Passive smoke exposure has been linked to reduced fertility in non-smoking partners and to poorer pregnancy outcomes. Both partners should aim to be smoke-free when trying to conceive.
Current evidence suggests that vaping is not a safe alternative. Many vaping products contain nicotine and other compounds that may affect reproductive health. The safer course is to aim for full nicotine cessation while trying to conceive.
Yes. Smoking is associated with a higher risk of miscarriage, both in natural pregnancies and in those achieved through assisted reproduction. The risk relates to both embryo quality and uterine environment.
Yes. Stopping before IVF improves ovarian response, embryo quality, implantation, and live birth rates. Earlier cessation is more beneficial, but quitting close to a cycle still helps.
Smoking during pregnancy raises the risk of miscarriage, placental complications, preterm birth, low birth weight, and certain neonatal complications such as sudden infant death syndrome.
Most fertility clinics and public health services offer structured cessation support, including counselling, behavioural therapy, and nicotine replacement therapy where appropriate. Combined support tends to be more effective than willpower alone.
Smoking is one of the most consistent themes across decades of reproductive research, and the picture is rarely flattering. Yet the same body of evidence that points to clear harm also points to clear, achievable improvement.
What stands out is not just the size of the effect, but the speed of the recovery. Within months of quitting, sperm quality begins to improve. The ovarian environment becomes more receptive. IVF outcomes shift in a favourable direction. Few areas of fertility offer such a clear return on a single decision.
The conversation about smoking and fertility is sometimes framed in terms of blame. A more useful framing is empowerment. Among the many factors that influence fertility, smoking is one of the few where the mechanism is well understood, the impact is significant, and the intervention is genuinely effective.
For anyone considering pregnancy or already on a fertility journey, the message from the science is steady and reassuring. The body responds. The numbers improve. The next chapter of your fertility story does not need to be defined by what came before, only by what you choose to do from here.
