Tobacco smoking may affect your chances of having a baby

Tobacco smoking may reduce the chances of having a baby. Its effects can begin before pregnancy and continue during pregnancy and after birth. The World Health Organisation highlighted these concerns in its knowledge summary, Tobacco and infertility, published on 8 September 2026.

WHO estimates that about one in six people of reproductive age experience infertility during their lifetime. Infertility means that pregnancy has not occurred after 12 months or more of regular, unprotected sexual intercourse. It can arise from problems in either partner, or from causes that remain unexplained.

Smoking and the chances of conception

Women who smoke may take longer to conceive. Smoking is associated with reduced fertility, earlier loss of ovarian function, miscarriage and ectopic pregnancy, where the pregnancy develops outside the uterus. These findings come mainly from observational studies. The size of the risk differs between studies, and smoking is only one of several factors that may affect fertility.

Smoking may also affect the results of fertility treatment, including in-vitro fertilisation (IVF). Studies have reported fewer pregnancies and live births among women who smoke. However, the findings are not uniform. A recent review found that the apparent reduction became less certain when the comparison was limited to women who had never smoked. It would therefore be misleading to tell every patient that smoking cuts her chance of successful treatment in half.

This advice should also apply to men. Smoking has been associated with poorer sperm concentration, movement and shape, and can contribute to erectile dysfunction. Poorer semen quality does not mean that every man who smokes is infertile. Its effect on the actual chance of fathering a child is less certain than the evidence of damage to semen quality.

During pregnancy

Pregnant and breastfeeding women should avoid all tobacco and nicotine products. This includes cigarettes, shisha, smokeless tobacco, heated tobacco, nicotine vapes and nicotine pouches, as well as nicotine patches, gum and lozenges. The aim is complete cessation of tobacco and nicotine. The absence of smoke does not remove the risks of nicotine exposure.

Smoking during pregnancy increases the risks of poor fetal growth, low birth weight, premature birth, placental complications and stillbirth. Nicotine can harm the developing brain and lungs. Quitting before pregnancy is best, but stopping at any stage of pregnancy can still benefit the mother and baby.

Breastfeeding and help with quitting

Nicotine and other harmful chemicals can pass to a baby through breast milk. Smoking can also reduce the mother’s milk supply. Exposure to second-hand smoke increases an infant’s risk of sudden infant death syndrome, respiratory illness and ear infections. Keep the home and car smoke-free, and family members should not smoke around the mother or baby.

A mother who is struggling to quit should receive help without blame. She should not stop breastfeeding simply because she smokes or vapes. CDC and NHS guidance advises continuing breastfeeding while working towards cessation, because breastfeeding still provides important benefits.

During pregnancy, the goal should be complete cessation of nicotine use, including nicotine replacement products. Help with quitting should focus on counselling, regular follow-up and practical support for managing cravings. A doctor or midwife can help a woman make a quit plan and provide individual care when stopping is difficult. Family members should support her efforts and keep the home free from tobacco smoke.

The role of less harmful alternatives

The discussion of less harmful alternatives applies to adult smokers who would otherwise continue smoking and who are neither pregnant nor breastfeeding. Much of the harm from cigarettes comes from burning tobacco and inhaling the resulting smoke. Nicotine causes dependence and has health effects of its own, but it is not the only harmful substance in a cigarette.

Completely replacing cigarettes with a regulated non-combustible alternative may reduce exposure to harmful substances. For example, a study comparing tobacco-use groups found lower levels of many toxicant biomarkers in people who used only e-cigarettes than in cigarette smokers. Exposure was not eliminated. This supports the potential to reduce harm from continued smoking, but does not establish the size of any reduction in long-term disease risk.

The Cochrane review of smoking-cessation studies also found that nicotine e-cigarettes helped more people stop smoking than nicotine replacement therapy in the trials reviewed. This is evidence about quitting cigarettes. It is not proof that vaping improves fertility or that it is harmless during pregnancy or breastfeeding.¹¹

Evidence for one product should not be applied to all nicotine products. Reproductive risks from newer alternatives remain incompletely understood. Continuing to smoke while using another product is not the goal; complete displacement of cigarettes is needed. Adults should receive cessation support, with eventual nicotine cessation where possible. Do not promote these products to young people or non-smokers, and ensure adult access through age checks, product standards, and marketing controls.

In Pakistan, doctors should ask both partners about tobacco and nicotine use during fertility consultations, antenatal visits and postnatal care. Advice should include second-hand smoke and practical help to quit. Couples need to understand the risks, but they also need support. Stopping tobacco use should be part of preparing for a baby, and that support should continue after the baby is born.