Nurturing life Your reference in perinatal nutrition, from pregnancy to childhood

During pregnancy, does cannabis consumption carry a risk for the baby?

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By : Nurturing Life's Nutrition Team | Montreal Diet Dispensary

Yes. The consumption of cannabis (marijuana) during pregnancy has risks for the foetus, even in small quantities.

Cannabis use should be avoided before, during and after pregnancy. First of all, the active ingredient in cannabis, THC (delta-9-tetrahydrocannabinol), is transmitted to the foetus through the placenta. This substance can remain in the body of the foetus for up to a month and a half after consumption, and can have adverse developmental effects. Marijuana today is stronger than before: it contains 300% to 400% more THC and very often other harmful products that vary according to the producer and seller.

On the other hand, cannabis has the same vasoconstrictive effects as cigarette, meaning that it reduces the size of blood vessels. Therefore, when the mother smokes marijuana, the foetus gets fewer nutrients and oxygen, which hinders its development.

Several risks (non-exhaustive) for the baby are associated with cannabis use during pregnancy:

  • low birth weight;
  • growth delay;
  • small size;
  • small head circumference;
  • learning disabilities, attention deficit, behaviour problems, memory loss and sleep disorders;
  • hyperactivity, impulsivity;
  • delinquency;
  • executive function disorders (planning, organization);
  • psychiatric disorders (anxiety, depression).

The effects on growth and risk of prematurity appear to be higher with more frequent exposure or long-term exposure compared to infrequent or short exposure. For example, a higher growth delay was observed when the mother used cannabis throughout her pregnancy. A slight decrease in the duration of pregnancy (premature birth) was also observed with a consumption of 5 or more times a week. The fact remains that any consumption, frequent or occasional, poses a foetal health risk. Even second-hand smoke is not without risk. For more information, see the following article (coming soon).

Abstinence is called for during pregnancy. If abstinence is not possible, a reduction in consumption should be considered with professional support to help the mother in this process.

It is important to always consult a doctor in case of addiction (drugs, alcohol, tobacco).


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