How Smoking and Vaping Affect Fertility in Men and Women

Smoking reduces fertility in both partners. In women it damages eggs, accelerates the loss of ovarian reserve and brings menopause forward; the American Society for Reproductive Medicine reports that women who smoke are up to twice as likely to experience infertility. In men it lowers sperm count and motility and increases DNA damage. Vaping is not a safe substitute, because it still delivers nicotine and other harmful compounds. Secondhand exposure carries risk too. Quitting works, and for men the improvement can appear within about three months as new sperm are produced.

How does smoking affect female fertility?

The chemicals in cigarette smoke reach the ovaries through the bloodstream and act on the eggs directly.

• Toxins including nicotine, cadmium and benzo[a]pyrene can damage the DNA inside eggs. Unlike many cells, eggs are not replaced, so this damage accumulates.
• Women who smoke reach menopause earlier than non-smokers, which reflects a faster loss of ovarian reserve.
• Younger women who smoke may have lower AMH levels, a marker of remaining egg supply.

What does it mean for IVF?

Women who smoke tend to respond less well to ovarian stimulation, often needing higher doses of medication while still producing fewer eggs. Research also reports lower fertilization and implantation rates and a higher risk of miscarriage compared with non-smokers. For couples trying naturally, the effect shows up as a lower chance of conceiving in any given month.

How does smoking affect male fertility?

• Sperm count and motility are lower in men who smoke.
• Abnormal sperm shapes are more common among smokers.
• Sperm DNA is more likely to be damaged, which can affect how an embryo develops.

The effect does not stop at fertilization. Partners of men who smoke experience higher miscarriage rates, and there is evidence that paternal smoking raises the risk of health problems in children, including respiratory illness. A semen analysis is the way to see where things stand.

Is vaping safer for fertility?

Vaping avoids the tar and combustion products of cigarettes, but it still delivers nicotine and other compounds, and it is not established as safe for reproductive health. The ASRM committee opinion on tobacco or marijuana use and infertility covers electronic nicotine delivery systems alongside conventional smoking. Treating vaping as a harmless alternative while trying to conceive is not supported by the evidence.

Does secondhand smoke matter?

Yes. Passive exposure delivers many of the same chemicals, including nicotine and carbon monoxide. Women exposed to secondhand smoke may experience reduced ovarian function and higher miscarriage rates, and men living with a partner who smokes may show changes in sperm quality without smoking themselves. Couples exposed to passive smoke during IVF cycles have been reported to have lower success rates.

What happens when you quit?

• For men, sperm quality can begin improving within about three months, because that is roughly how long a cycle of sperm production takes.
• For women, stopping before IVF is associated with a better response to medication and better outcomes than continuing. Damage already done to the ovarian reserve is not reversed, which is why stopping sooner matters more than stopping perfectly.
• For the pregnancy, quitting reduces the risk of miscarriage and of complications later.

Nicotine replacement such as patches or gum, and behavioral support, both help. Setting a quit date together tends to work better than one partner going it alone, because a household where one person still smokes leaves the other with passive exposure.

We at Millennium IVF Clinic assess both partners rather than one. You can arrange a consultation with our team.

Frequently asked questions

How long before trying to conceive should I stop smoking?

As early as possible. For men there is a practical marker in that sperm production takes roughly three months, so quitting at least that far ahead allows the improvement to show. For women there is no threshold at which damage to the ovarian reserve reverses, so earlier is simply better.

Is nicotine replacement therapy safe while trying to conceive?

Nicotine replacement removes exposure to the other combustion products of smoking, which is why it is used to support quitting. Discuss its use with your doctor, particularly if you may already be pregnant.

Does smoking affect IVF success specifically?

Yes. Women who smoke tend to need more medication, produce fewer eggs, and have lower fertilization and implantation rates with a higher miscarriage risk.

My partner smokes but I don't. Does that affect us?

It can. Secondhand exposure has been linked to reduced ovarian function and higher miscarriage rates, and to lower IVF success in exposed couples.