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Statistics and Facts
What is in a Cigarette?
One cigarette contains over 8000 chemicals. Many of them cause cancer.  Some of the chemicals are: cyanide, DDT, arsenic, lead and formaldehyde. These chemicals are also found in rat poison, gasoline, paint thinner, insecticide and car batteries.
Cigarettes also contain carbon monoxide- one of the most harmful parts of smoking. Carbon monoxide replaces some of the oxygen in the blood. As a result, many of the vital organs (heart, brain, and kidney) do not get the blood, nourishment or oxygen they need.
The chemicals found in cigarettes are also called tars. Tar is the brown, sticky part of the cigarette that stains the teeth, fingers and nails. Tar increases the risk of many kinds of cancers including: lung, breast, colon, kidney, stomach, cervical, esophagus, mouth, throat, bladder and pancreas. Smoking is the cause of 30% of all cancers in Canada and 85% of lung cancers.
Tar collects in the airways within the lungs. The build-up of tar in the lungs can lead to many diseases such as emphysema, bronchitis, chronic obstructive pulmonary disease (COPD), asthma, and pneumonia.
Nicotine is addictive, but it is not the most harmful part of a cigarette. This is why using nicotine replacement therapy (NRT) such as the patch or gum is a safe choice if you need help with reducing or quitting smoking. When you use NRT, you only get the nicotine and not the other tars or chemicals in cigarettes. NRT can help reduce withdrawal symptoms and increase the chances of quitting. Speak to your doctor, nurse, midwife or doula about whether it is safe for you to use NRT.
Ontario Statistics 
  • In 2013: 14% of women in Ontario were smokers. 
  • In 2011–2012 in Ontario, 9% of women said they smoked during pregnancy at 20 weeks’ pregnant or later1  
  • Research from 2006- 2009 shows:2
    • The percent of women who smoke in Ontario is different in different regions. For example 5% of pregnant women smoke in Toronto, 15% in Eastern Ontario and 34% in North Western Ontario 
    • Pregnant women younger than 20 years old are more likely to smoke during pregnancy 
    • Pregnant women who smoke are more likely to have gone to school for less time than pregnant women who do not smoke 
    • Pregnant women who smoke are more likely to have asthma, a history of depression, a history of anxiety and alcohol dependence 
    • Babies born with very low birth weights are more likely to be born from mothers who smoked during the pregnancy  
Canadian Statistics
  • Research studies show that when people tell others how much they smoke, it is less than what they actually smoke. 23-28% of pregnant women who smoke do not admit it when asked.3-4 
  • For Canadian women who smoke in the last three months of their pregnancy, 42.4%  smoked 10 or more cigarettes per day while 57.6% smoked 1 to 9 cigarettes per day.4
  • Smoking is higher among Canadian women with more than one child (11.9%) than those with only one child (9.1%).4
  • Data shows that women are more likely to quit smoking or smoke fewer cigarettes during pregnancy than at any other time in their lives. Quitting or reducing is generally out of concern for the health of the baby.5-6
  • Right after giving birth, 85% of women return to smoking.  In Canada, 47% of mothers who quit smoking during their pregnancy start smoking again daily or occasionally after giving birth.7 
If you have questions, you can read our Common Questions or How to Talk to Your Healthcare Provider pages.  
  1. BORN Ontario. 2011-2012 Better Outcomes Registry & Netowrk Program Report. Accessed February 13, 2015 from
  2. Echo Improving Women’s Health in Ontario. May 2011. Smoking Cessation Best Practices for Pregnant Women: Adapting to Local Needs. Echo Advance. Toronto, Ontario. 
  3. Webb DA, Boyd NR, Messina D, Windsor RA. The discrepancy between self-reported smoking status and urine continine levels among women enrolled in prenatal care at four publicly funded clinical sites. Journal of Public Health Management & Practice. Jul-Aug 2003;9(4):322-325.
  4. Dietz PM, Homa D, England LJ, et al. Estimates of nondisclosure of cigarette smoking among pregnant and nonpregnant women of reproductive age in the United States. American Journal of Epidemiology. Feb 1 2011;173(3):355-359.
  5. Crawford JT, Tolosa JE, Goldenberg RL. Smoking cessation in pregnancy: why, how, and what next. Clinical Obstetrics & Gynecology. 2008;51(2):419-435.
  6. Ingall G, Cropley M. Exploring the barriers of quitting smoking during pregnancy: a systematic review of qualitative studies. Women & Birth: Journal of the Australian College of Midwives. 2010;23(2):45-52.
  7. Fang WL, Goldstein AO, Butzen AY, et al. Smoking cessation in pregnancy: a review of postpartum relapse prevention strategies. Journal of the American Board of Family Practice. Jul-Aug 2004;17(4):264-275.