Smoking is widely known to have harmful effects on overall health, increasing the risk of various cancers and cardiovascular diseases. However, its impact on reproductive health is often overlooked. Both men and women can experience reduced fertility due to smoking, and it can also lead to complications during pregnancy. In this article, we will explore how tobacco use affects fertility, assisted reproduction, and pregnancy.
How Does Smoking Affect Female Fertility?
Smoking has been linked to decreased fertility in women, although the exact mechanisms remain unclear. It is believed that tobacco use may interfere with ovarian hormone production, damage the genetic integrity of oocytes, and impair the function of the fallopian tubes. Additionally, uterine receptivity may also be negatively affected.
As a result, women who smoke often experience a longer time to conceive compared to non-smokers. Notably, even passive smoking (exposure to secondhand smoke) can reduce fertility.
Another major consequence of smoking is its association with an earlier onset of menopause, occurring between one to four years earlier than in non-smokers. This is especially significant today, as many women are delaying childbirth.
The extent of smoking’s impact on fertility appears to be dose-dependent, meaning that the more cigarettes a woman smokes per day, the greater the damage. However, quitting smoking can partially reverse some of the negative effects.
For this reason, any woman who plans to have children in the future should avoid smoking entirely or quit as soon as possible.
How Does Smoking Affect Male Fertility?
Smoking also negatively impacts male fertility by reducing sperm quality. The most affected sperm parameters are sperm concentration and motility, though the degree of impact depends on the number of cigarettes smoked daily.
In addition to sperm quality, smoking can lead to other reproductive complications in men, including:
• Hormonal imbalances
- Disruptions in spermatogenesis (sperm production), sperm maturation, and function
- Oxidative stress, caused by an increase in reactive oxygen species (ROS), which can lead to sperm DNA damage and fragmentation
• A higher risk of erectile dysfunction
Given these adverse effects, quitting smoking can significantly improve male fertility and increase the chances of conception.
Does Smoking Affect Assisted Reproduction?
Effects on Female Patients Undergoing Assisted Reproduction
Women who smoke and undergo assisted reproductive treatments often experience a lower response to ovarian stimulation and require higher doses of hormone medication to induce ovulation. Despite this, they tend to produce fewer oocytes (eggs), and the rate of canceled cycles may be higher.
In addition, smoking has been shown to negatively affect the success rates of assisted reproductive techniques, reducing both clinical pregnancy rates and live birth rates.
Effects on Male Patients Undergoing Assisted Reproduction
The impact of male smoking on assisted reproduction outcomes is less clear. One challenge in studying this effect is that male smokers often expose their partners to secondhand smoke, making it difficult to separate the direct impact on sperm from the indirect effects on the female partner.
However, given that smoking can reduce sperm concentration, motility, and normal morphology, it may negatively influence treatments like artificial insemination (AI) and in vitro fertilisation (IVF).
The Impact of Smoking on Pregnancy
Beyond fertility issues, smoking during pregnancy is associated with serious obstetric complications that can jeopardise both maternal and fetal health. The major risks include:
- Ectopic pregnancy (when a fertilised egg implants outside the uterus)
- Miscarriage (spontaneous abortion)
- Intrauterine growth restriction (IUGR)
- Placenta previa (a condition where the placenta covers the cervix, leading to complications)
- Premature rupture of membranes (PROM)
• Preterm birth • Low birth weight
• Perinatal mortality (death of the baby around the time of birth)
Additionally, studies suggest that maternal smoking during pregnancy may negatively impact the sperm quality of male offspring later in life.
Recommendations for Smokers Who Want to Conceive
The most important recommendation is simple: do not start smoking. However, if a person is already a smoker, quitting as soon as possible is the best course of action.
Quitting smoking can be challenging, and individuals who struggle should not hesitate to seek medical advice and support.
Additionally, other unhealthy lifestyle habits—such as excessive alcohol consumption and drug use—should also be avoided to improve reproductive health.
On the other hand, adopting healthy habits can have a positive impact on fertility, such as:
• Eating a balanced and nutritious diet • Engaging in moderate exercise • Maintaining a healthy body mass index (BMI)
These lifestyle changes not only benefit overall well-being but also enhance fertility for both men and women.
Frequently Asked Questions (FAQs)
- Does quitting smoking improve assisted reproduction outcomes?
By Dr. Guillermo Quea Campos (Gynecologist)
Yes. Quitting smoking improves the reproductive potential of individuals or couples seeking to conceive.
- Does smoking affect artificial insemination (AI)?
By Dr. Guillermo Quea Campos (Gynecologist)
Yes, almost all research confirms that smoking has a negative effect on fertility.
Studies show that women who smoke take longer to conceive than non-smokers. Additionally, smoking accelerates egg loss and reproductive decline, potentially leading to earlier menopause.
In men, smoking leads to reduced sperm count, lower motility, and abnormal sperm morphology, which may disqualify some individuals from undergoing artificial insemination. For women, the reduced quality and quantity of eggs also compromises success rates in AI treatments.
- Does smoking decrease fertility?
By Silvia Azaña Gutiérrez, B.Sc., M.Sc. (Embryologist)
Yes. Smoking is harmful to fertility in both men and women.
In men, smoking contributes to lower sperm quality, increased sperm DNA fragmentation, and erectile dysfunction.
In women, smoking prolongs the time to conception and may lead to earlier menopause (by 1–4 years) compared to non-smokers.
- Can vitamins help counteract the effects of smoking on male fertility?
By Silvia Azaña Gutiérrez, B.Sc., M.Sc. (Embryologist)
The best way to mitigate the effects of smoking on male fertility is to quit smoking altogether.
After quitting, certain vitamin supplements—especially those rich in antioxidants like vitamins C and E—may help reduce oxidative stress and improve sperm health.
However, it is crucial to consult a specialist before taking any supplements to ensure the correct dosage and appropriate treatment plan.
Conclusion
Smoking has severe consequences for fertility in both men and women. It can prolong the time to conception, reduce sperm and egg quality, and lower the success rates of assisted reproductive treatments. Moreover, smoking during pregnancy increases the risk of serious complications that can endanger both the mother and baby.
Fortunately, quitting smoking can significantly improve reproductive outcomes. Whether a person is planning for a future pregnancy or undergoing fertility treatments, stopping smoking is one of the best steps they can take to enhance their chances of conception and ensure a healthy pregnancy.