Cannabis & Pregnancy

The substances in cannabis are carried through the mother’s blood to her fetus during pregnancy. They are passed into the breast milk following birth. This can lead to health problems for the child.


Cannabis use during pregnancy can lead to lower birth weight. It has also been associated with longer-term developmental effects in children and adolescents, such as:


Decreases in:

  • Memory function
  • Ability to pay attention
  • Reasoning and problem solving skills
  • Hyperactive behaviour


Increases in:

  • Risk for future substance use

Cannabis & Youth

Research shows the brain is not fully developed until around age 25. Thus, youth are especially vulnerable to the effects of cannabis on brain development and function. The THC in cannabis affects the same biological system in the brain that directs brain development.


Cannabis use has been associated with increased risk of harms when it:

  • Is frequent
  • Continues over time
  • Begins early in adolescence


Resources are available for youth.

Cannabis & Mental Illness

In some people, cannabis use increases the risk of developing mental illnesses such as psychosis or schizophrenia, especially those who:

  • Start using cannabis at a young age
  • Use cannabis frequently (daily or almost every day)
  • Have a personal or family history of  psychosis and/or schizophrenia


Frequent cannabis use has also been associated with an increased risk of:

  • Suicide
  • Depression
  • Anxiety disorders
  • Hyperactive behaviour
  • Increased risk for future substance use


Help resources are available.

Cannabis & The Body

Short Term Effects

Effects of cannabis on the body can include:

  • Damaged blood vessels caused by smoke
  • Decreased blood pressure, which can cause people to faint or pass out
  • Increased heart rate, which can be a danger for people with heart conditions and can lead to an increased risk of heart attack

Cannabis & The Body

Long Term Effects

Effects of smoking cannabis are similar to the effects of smoking tobacco and can include risks to lung health, such as:


  • Bronchitis 
  • Lung infections 
  • Chronic (long-term) cough 
  • Increased mucus buildup in the throat

Cannabis & The Brain

Long Term Effects

Effects of cannabis on the brain can include an increased risk of addiction and harm to your: 

  • Memory and concentration 
  • Intelligence (IQ) 
  • Ability to think and make decisions


These effects appear to be worse for youth who start using early, and those who use cannabis frequently and over a long period of time. Effects may not be fully reversible when cannabis use stops.