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Substance Use in Pregnancy

Home Health and Wellness PregnancySubstance Use in Pregnancy

Using drugs while you are pregnant or breastfeeding can harm you and your baby

It is important to take care of yourself and stay as healthy as you can during pregnancy.

Marijuana in pregnancy

Marijuana comes from the cannabis plant. It is also known as

Pot
Hash
Mary jane
Weed

There is no safe amount of marijuana to use during pregnancy or breastfeeding. Marijuana reaches your baby during pregnancy. It also reaches them through breastmilk when breastfeeding.

Marijuana can stay in your baby's brain for weeks. Marijuana is not a safe treatment for nausea and vomiting in pregnancy. Talk to your doctor or healthcare provide about safer treatments.

Cannabis and pregnancy infographic

Using marijuana in pregnancy is not safe because:

Your baby might not get enough oxygen to grow normally.
Your baby can be born too soon, or too small.
Your baby can have health problems.
Your baby can have withdrawal signs, like problems sleeping after birth.

Using marijuana in pregnancy can affect your child's:

Memory and learning
Problem-solving skills
Emotions and behaviour
Ability to focus and pay attention

To learn more about marijuana in pregnancy, read Best Start's resource on the risks of cannabis.

Opiates in pregnancy

Taking opiates during pregnancy can be harmful to your baby.

Opiates are a type of drug or medication, such as:

Oxycodone
OxyNeo
Percocet
Fentanyl
Tylenol #3
Heroin
Morphine
Demerol

If you suddenly stop taking opiates during pregnancy, you might go into early labour. It is important to slowly stop opiates when you are pregnant. Talk to your doctor or health care provider about any medications or drugs you are taking during pregnancy.

Learn more about pregnancy and opioids.

Smoking in pregnancy

Smoking or breathing second-hand smoke while you are pregnant is harmful to you and your baby. Smoking can cause your baby to be born too small or too early. Babies born too early can have more health problems. Early birth might cause trouble eating or sleeping.

A smoke-free home is the best place for you and your baby. Second-hand smoke (the smoke you breathe if someone else smokes) is also harmful to you and your baby. If your partner or friends are smoking, ask them to smoke outside.

If you are pregnant, try to stop smoking. If you cannot quit, try to smoke fewer cigarettes. Quitting smoking is not easy. It is important to get help and support. Talk to your doctor or health care provider.

Are you thinking of quitting smoking?

It is easier to quit smoking if the people around you do not smoke. Quitting smoking early in pregnancy can help your baby grow a healthy body. It is never too late to quit smoking. Help is available.

For more information, read Smoking During Pregnancy.
Learn more about Making Your Home Smoke Free.

It is important to find help from someone you trust. Talk to your doctor or health care provider about any substances you are using during pregnancy.

More resources

Smokers' Helpline 1-877-513-5333
Health Canada Go Smoke Free