Cannabis use before or during pregnancy, or while breastfeeding

Learn about using cannabis while you are trying to get pregnant, are pregnant, or breastfeeding. Get information to help make healthy decisions for yourself and your baby.

On this page

• Important information about cannabis use during pregnancy and breastfeeding
• Talking to your health care provider about cannabis
• About cannabis
• Before pregnancy
• During pregnancy
• Breastfeeding
• Tips to reduce the risk of harm to yourself and your child
• Healthy pregnancy resources

Important information about cannabis use during pregnancy and breastfeeding

• Using cannabis while pregnant or breastfeeding can harm your baby's growth and development.
• There's not enough research to identify a "safe amount" of cannabis that you can use during pregnancy or breastfeeding.
• The safest choice is to not use cannabis when pregnant or breastfeeding.
• If you use cannabis, you can help lower the risk of harm to yourself and your baby by reducing or stopping your use. Your health care provider can help you find an approach and supports that work for you.
• Chemicals in cannabis—such as THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol)—cross the placenta and pass into breast milk to your baby.
• Edibles and vaping aren't safer alternatives to smoking cannabis during pregnancy or breastfeeding.
• Cannabis isn't recommended to treat morning sickness.

Talking to your health care provider about cannabis

Your health care provider can recommend supports and resources, and provide help based on your specific situation.

If you're thinking about getting pregnant, are pregnant, or breastfeeding and aren't comfortable having conversations with your health care providers about your cannabis use, you can use this resource to guide your conversation:

• Starting health care conversations: Cannabis, pregnancy, and breastfeeding and chestfeeding (Canadian Centre on Substance Use and Addiction)

About cannabis

Cannabis is also known as marijuana, weed and pot. The cannabis plant has hundreds of chemical compounds, including:

• THC, the compound that makes people feel high
• CBD, the compound that doesn't make people feel high, but still effects the brain and body in ways that are being researched for possible therapeutic uses

Cannabis products come in different forms such as:

• oils
• vapes
• rolled joints
• edible products

They can contain different amounts of THC, CBD, and other compounds.

You can feel the effects of inhaled products quickly, while it may take longer for you to feel the effects of edible products because they must be digested.

Learn more:

• About cannabis
• Health effects of cannabis
• Cannabis in Canada: Get the facts
• Cannabis use and caring for young children
• Your questions about cannabis, pregnancy and breastfeeding and chestfeeding (Canadian Centre on Substance Use and Addiction)

Before pregnancy

Cannabis use may affect:

• menstrual cycles
• sperm count and quality
• the ability to get pregnant

If you're thinking about getting pregnant, talk to your health care provider about your cannabis use.

During pregnancy

Using cannabis when you're pregnant can increase the risk of certain health impacts for you and your baby.

For your baby, this includes:

• being born early, having a low birth weight and being small for gestational age
• having to go to the neonatal intensive care unit (NICU)
• lower scores on tests used to check breathing, heart rate, and overall health right after birth (Apgar scores)
• possible birth defects (for example, heart, central nervous system, gastrointestinal anomalies)
• longer hospital stays ^{Footnote 1 Footnote 2 Footnote 3}

Using cannabis during pregnancy may affect how your child's brain develops. It may also affect their behaviour, learning, and mental health. Some of these effects may continue into their teenage years and early adulthood. The risks may be higher if you use cannabis often during pregnancy, such as every day. Possible effects on your child's health and development include:

• sleep problems
• delays in thinking and learning skills during early childhood
• difficulties with learning, memory, and behaviour
• acting without thinking (impulsive), being very active (hyperactive), trouble paying attention
• mental health concerns, such as anxiety or depression
• difficulties with planning, making decisions, and solving problems
• a higher chance of using substances, including cannabis, at a younger age

For you, this includes:

• anemia
• weight gain
• preeclampsia
• longer hospital stays
• gestational hypertension
• poor placenta blood circulation^{Footnote 4}
• increased risk of postnatal depression and anxiety^{Footnote 5}

You may experience morning sickness (nausea and vomiting) while pregnant. Cannabis isn't recommended to treat morning sickness or for other medical reasons while you're pregnant because of the risks to you and your baby. Although cannabis is a natural plant, it doesn't make it safe during pregnancy.

If you're pregnant, talk with your health care provider about cannabis use and safer treatment options.

Breastfeeding

All forms of cannabis pass into breast milk. Cannabis can remain in breast milk for days to weeks after you use it. THC in breast milk may affect your baby's ability to breastfeed as it can make them drowsy or have difficulty latching and sucking. Using cannabis while breastfeeding may also impact your child's brain development, behaviour, and mental health.

Because cannabis can remain in your body for a long time, expressing or pumping breast milk then discarding it ("pumping and dumping") doesn't help to reduce cannabis in your breast milk.

The safest choice is to not use cannabis if you're breastfeeding until we know more about all the effects of cannabis use on maternal and infant health.

If you're breastfeeding, talk to your health care provider about your cannabis use.

Tips to reduce the risk of harm to you and your child

It's safest to avoid using cannabis when planning a pregnancy, pregnant or breastfeeding.

If you use cannabis, reducing or stopping your use can help lower the risk of harm to you and your baby. You can do this by:

• using cannabis less often
• using less cannabis at a time
• buying only legal cannabis products
• not driving during or after using cannabis
• using cannabis products with lower THC levels
• not mixing cannabis with other substances, such as alcohol

Canada's lower-risk cannabis use guidelines

Healthy pregnancy resources

Having a baby can be a wonderful experience, but it can also be a time of uncertainty. Many parents have questions and concerns as they face all the changes that pregnancy brings. With advice coming from everyone, it's tough to know who to listen to. That's why having accurate information is so important. It will help you to make informed decisions about how to take care of yourself before, during, and after your pregnancy.

Learn more:

• Your guide to a healthy pregnancy
• Your guide to postpartum health and caring for your baby
• Nausea and vomiting (Society of Obstetricians and Gynaecologists of Canada)
• Getting started: Why health before pregnancy matters (Society of Obstetricians and Gynaecologists of Canada)
• The facts on pregnancy and childbirth from Canada's experts (Society of Obstetricians and Gynaecologists of Canada)