Smoking and fertility
Can smoking affect my ability to have a baby?
Most people understand that smoking is “bad for you” as it increases your risk of heart, vascular and lung disease. However, many people do not know that smoking can directly affect fertility in both men and women.
How does smoking affect eggs or sperm?
Chemicals (such as nicotine, cyanide and carbon monoxide) in cigarette smoke accelerate the rate of egg loss. Unfortunately, once the eggs die, they cannot be regenerated or replaced. This means that menopause occurs 1 to 4 years earlier in women who smoke (compared to non-smokers). Male smokers may suffer from reduced sperm quality with lower sperm count (sperm concentration) motility (ability of sperm to move) and increased numbers of sperm with an abnormal shape. Smoking can also reduce the ability of sperm to fertilise eggs.
How can smoking affect your ability to conceive?
Women who smoke do not arrest as effectively as non-smokers. In fact, infertility rates in female smokers are about twice as high as in non-smokers, and the risk increases with the number of cigarettes smoked daily. At this point we should also mention that even fertility treatments such as IVF have lower success rates in female smokers. More specifically, female smokers need more ovarian stimulating drugs during IVF, have fewer eggs and 30% lower pregnancy rates compared to patients undergoing IVF who do not smoke. Finally, because smoking damages the genetic material in the eggs and sperm, the rates of miscarriages and birth defects in the embryos are higher. Women who smoke are more likely to conceive an embryo with a chromosomal abnormality (e.g. Down’s syndrome) than non-smokers. Extrauterine pregnancies and preterm birth also occur more frequently in women smokers.
Can smoking affect pregnancy?
Interestingly, studies show that men whose mothers smoked half a pack of cigarettes (or more) a day during pregnancy have lower sperm counts. Smoking during pregnancy can also lead to restricted growth of the baby and a lower than expected birth weight. Children born with a lower than expected birth weight are at greater risk of medical problems later in life (such as diabetes, obesity and cardiovascular disease).
If I stop smoking, will my chances of conceiving and having a healthy pregnancy improve?
Yes. Quitting smoking can improve fertility and is the first thing we advise as fertility experts. It is true that quitting smoking can be very difficult, but studies show that the chance of success is much higher if the patient is referred to specialist smoking cessation clinics . Sometimes, the temporary use of a nicotine substitute (such as gum or nicotine patch) or even some specific medications, can improve smoking cessation rates, as they can also be used during conception if needed. On the other hand, substitutes such as e-cigarettes are best avoided, as recent studies question their “innocence”. In conclusion, the negative impact of cigarettes on fertility is well established. Scientific evidence supports the value of a proactive approach to fertility, discouraging smoking and exposure to cigarette smoke in both women and men. As physicians, we must facilitate smoking cessation by providing education, monitoring and individualized support.
References
- Lyngsø J, Kesmodel US, Bay B, Ingerslev HJ, Pisinger CH, Ramlau-Hansen CH.
Female cigarette smoking and successful fertility treatment: a Danish cohort study.Acta Obstet Gynecol Scand. 2021 Jan;100(1):58-66 - Oboni JB, Marques-Vidal P, Bastardot F, Vollenweider P, Waeber G.
Impact of smoking on fertility and age of menopause: a population-based assessment. BMJ Open. 2016 Nov 18;6(11):e012015 - Bardhi E, Drakopoulos P. Update on Male Infertility J Clin Med. 2021 Oct 18;10(20):4771
- Practice Committee of the American Society for Reproductive Medicine.
Smoking and infertility: a committee opinion.Fertil Steril. 2018 Sep;110(4):611-618
