Quitting Smoking During Pregnancy

This page is general information from public health sources, not medical advice. Tell your doctor, midwife, nurse practitioner or pharmacist if you smoke. They can help without judgment.

Is it safe to quit smoking while pregnant?

Yes, and Health Canada encourages it at any stage. Quitting before conception or early in pregnancy gives the greatest benefit to the baby and to you, but quitting at any point in pregnancy still provides significant health benefits. Health Canada says quitting reduces the effect of smoke on the baby’s growth and lowers the risk of a baby who is smaller than usual.

What does smoking do to a pregnancy?

Health Canada says toxic chemicals from tobacco smoke pass from the mother to the baby through the placenta. Smoking or smoke exposure during pregnancy raises the risk of preterm delivery and of placental complications, including placental abruption and placenta previa, which can require emergency care. Carbon monoxide can slow the baby’s growth, and nicotine can reduce blood flow through the placenta and affect the developing lungs and brain.

Babies of mothers who smoked may have low birth weight, which Health Canada defines as under 2.5 kg (5.5 lb). Smoke exposure during and after pregnancy also raises the risk of sudden infant death syndrome (SIDS). In 2021, 5% of Canadian women aged 15 to 55 who had been pregnant in the previous five years reported smoking while pregnant, according to the Canadian Community Health Survey as cited by Health Canada.

What can I use to quit?

1. Counselling first. Health Canada’s guidance for pregnancy and breastfeeding is to start with counselling. The free pan-Canadian quit line is 1-866-366-3667, and your province’s service is in our free quit help by province table.
2. Nicotine replacement if counselling is not enough. Health Canada says to speak with a health care provider. It prefers short-acting forms (gum, inhaler, spray, lozenge) to the patch. British Columbia’s clinical guideline for clinicians agrees that behavioural support is first-line and says that when a risk-benefit assessment supports medication, nicotine replacement appears to be the safest choice.
3. Anything else. Health Canada’s pregnancy guidance names only counselling and nicotine replacement. Ask your provider before using any other product or medication.

For how replacement products work and what provinces cover, see medications to quit smoking in Canada.

What about vaping or other people’s smoke?

Health Canada’s page on smoke and pregnancy does not cover vaping, so we do not make claims about it here; ask your provider. On other people’s smoke it is clear: there is no safe level of exposure, a baby should be kept away from tobacco smoke in all enclosed spaces (home, vehicles, building entrances, work), and air cleaning, filtering, better ventilation and separate smoking areas do not remove the risk. If someone at home smokes, the guide to quitting when someone at home smokes and the second-hand smoke hub are useful next steps.

How likely is it to work, and what about after the birth?

The Public Health Agency of Canada reports on the Maternity Experiences Survey of women who delivered in 2006. Of those, 22% smoked just before pregnancy and 11% in the third trimester, and 53% of women who smoked at the start of pregnancy had quit by the third trimester. That is a dated figure, but it shows quitting is common. It also found that 47% of women who quit during pregnancy relapsed after the birth.

That second number is the reason to plan ahead. Line up support for the weeks after delivery, keep the first-week quit routine handy, and tell the people around you how they can help someone quit smoking.