The Potential Effects of Cannabis during Pregnancy

Health advice

To learn more about cannabis, read the previous part — Cannabis Use by a Pregnant Woman.

Article updated June 1, 2023.

Many potential effects of cannabis use during pregnancy exist. Like for tobacco, cannabis use by a pregnant woman can affect the fetus and lead to health problems. Cannabis, like nicotine, constricts blood vessels (narrowing the vessels) which can limit the transmission of nutrients and oxygenation to a baby in full growth. Furthermore, second-hand smoke isn’t danger-free. Cannabis intolerance can lead to acute abdominal pain, which ceases only when the drug is stopped. Cannabis toxins are transported by the pregnant woman’s blood to the fetus, and can also be found in breast milk.

Heavy use of cannabis during pregnancy can mean that the drug invades the developing baby’s brain and impacts its normal development (cognitive and behavioural development). Cannabis use can also have a negative impact on breast milk production by inhibiting prolactin secretion.

Potential impacts on the pregnancy:

  •    Miscarriage risk (spontaneous abortion)
  •    Premature labour risk (if consumed heavily and regularly)

Possible effects on the fetus:

 If the pregnant woman uses both tobacco and cannabis, the impact on the baby is increased.

At birth:

  • Smaller head circumference (smaller cranial perimeter)
  • Growth delays
  • Low birth weight
  • Sleep disorders
  • Deprivation or withdrawal symptoms (trembling, irritability, slower reflexes, less reactive)
  • May have a cognitive impairment

Longer term (child or adolescent):

The brain develops until the age of 20 and can be influenced at any time. Children aren’t less intelligent, but effects may show up at different times over their lives, sometimes between 10 and 15 years:

  • A lowering:

        – Of memory capacity (memory problems)

        – Of concentration capacity (attention disorder)

        – Of reasoning and problem-solving skills

  • Hyperactivity
  • Learning and behavioural disorders (impulsivity)
  • Mental health problems, mood issues (anxiety, depression)
  • Increased risk of addiction problems in the future

To read the last part of this article, go to Fathers, Cannabis and Pregnancy.

Discover our videos

Subscribe to a monthly or quarterly package now to access full videos.

Bathing a Newborn

Bathing a Newborn

You might feel insecure giving a newborn a bath. Marie demonstrates a newborn bath massage with baby Romain. After watching

Clearing the Airways

How to know if your baby is at risk of choking or suffocating? What should you do if your baby
Sexuality and Pregnancy

Sexuality and Pregnancy

Can having sex at the start of pregnancy cause a miscarriage? When your stomach is sticking out, how can you
Good Lifestyle Habits and Pregnancy

Good Lifestyle Habits and Pregnancy

As a future mother, you want to do your best to promote the proper development of your baby. Here are

Discover other articles

Almost 36 weeks pregnant!

Almost 36 weeks pregnant!

Make sure you read the previous part of the story – I am slowly getting back to normal at my own pace. Assurez-vous de lire
Insufficient or Low Levels of Breast Milk

Insufficient or Low Levels of Breast Milk

In this entry, I will talk about the circumstances that might lead to low milk production.
Worries and Levels of Anxiety

Worries and Levels of Anxiety

Worrying can be defined as a train of thoughts difficult to control accompanied by negative emotions.
Who is the midwife?

Who is the midwife?

A midwife is a health professional working with future parents during a healthy pregnancy. They monitor them through childbirth and after the birth of the

The Potential Effects of Cannabis during Pregnancy

Par Marie Fortier Temps de lecture: 1 min