EFFECTS ON PREGNANCY

Understanding pregnancy & cannabis

As cannabis legalization spreads and usage increases across all age groups, understanding THC’s physical, mental, and emotional impacts is crucial. This knowledge helps people make safe, informed choices, particularly during pregnancy, when decisions affect both the mother and the fetus. To support a healthy pregnancy, it is essential to avoid substances like cannabis, alcohol, tobacco, and other drugs. In this section, we will present evidence on cannabis use during pregnancy to help parents and their support networks make informed decisions, ensuring the best outcomes. While The Tea on THC focuses on high concentration cannabis, this evidence applies to all forms and concentrations of cannabis, with higher THC levels being linked to greater health risks.

How cannabis impacts both sides of the pregnancy

Cannabis contains over 500 chemicals, with at least 60 interacting with the nervous system. The medicinal and psychoactive effects are due to cannabinoids, which are absorbed through the lungs when smoked or the digestive tract when eaten, binding to brain receptors. Evidence shows that some cannabinoids can pass through the placenta, potentially harming the fetus’s development and increasing pregnancy complications.

Cannabidiol (CBD)

Does not produce a psychoactive effect

Facilitates drug passage to the fetus

Reduces uterine blood flow, affecting placenta

Tetrahydrocannabinol (THC)

Produces a psychoactive “high” effect

Potentially crosses placenta, accumulates in fetal brain

Other Contaminants

Cannabis contaminants can expose the fetus to toxins, including insecticides and mold

The prevalence of cannabis use during pregnancy

Researchers are finding that THC is increasingly being used during pregnancy across all age groups, with rates particularly high among younger, urban, and socioeconomically disadvantaged people. National surveys indicate a doubling in reported cannabis use among pregnant women from 2002 to 2017, with usage rates ranging from 2% to 5% overall, and skyrocketing to 15% or even 28% in certain demographics. Study after study reveals a persistent rise in cannabis consumption during pregnancy.

Factors associated with cannabis use during pregnancy:

Under 25 years old

Lower household income

Other substance use, including cigarettes

Endured significant emotional distress

Unemployment

No high school diploma

Previous cannabis dependence

Myth	Fact
Cannabis is safer and less expensive than tobacco.	For the fetus, cannabis poses risks similar to tobacco.
Cannabis is a safe and effective treatment for morning sickness.	No evidence supports this claim.
There is no risk, or just a slight risk, to using cannabis only once or twice a week during pregnancy.	Researchers already know that THC poses risks to fetal development, including to the nervous system. Research is still being conducted, but cannabis experts don’t think there is any "safe" dose during pregnancy.

  Myth
    Fact
  
      Cannabis is safer and less expensive than tobacco.
      For the fetus, cannabis poses risks similar to tobacco.
    
      Cannabis is a safe and effective treatment for morning sickness.
      No evidence supports this claim.
    
      There is no risk, or just a slight risk, to using cannabis only once or twice a week during pregnancy.
      Researchers already know that THC poses risks to fetal development, including to the nervous system. Research is still being conducted, but cannabis experts don’t think there is any "safe" dose during pregnancy.

Cannabis use during pregnancy: Risks to the pregnant person

Impaired judgment and coordination: Can affect motor skills and cognitive functions, leading to dizziness and falls.

Impaired breathing and lung function: Smoking cannabis can lower oxygen levels in the body, increasing the risk of breathing problems and lung damage.

Mental health effects: Frequent cannabis use (or use of high concentration products) can elevate the risk of mental health issues such as anxiety, paranoia, psychosis, schizophrenia, depression, and suicide.

Legal repercussions: Some hospitals in Colorado test newborns for drugs, including cannabis, and may notify child protective services of a positive result.

Cannabis use during pregnancy: Risks to fetuses and newborns

Fetuses exposed to cannabis in the womb may suffer:

Fetal growth restriction
Premature birth
Low birth weight
Smaller birth length
Smaller head circumference
Admission to the neonatal intensive care unit
Stillbirth

Factors associated with these risks are:

Frequent cannabis use (at least weekly)
Combined use of cannabis and tobacco
Use during the first and second trimesters

Cannabis use in pregnancy: Risks in infancy to young adulthood

9 months: Impaired mental development
4 years: Lower scores in executive function tasks
6 years: Deficits in various cognitive functions, increased impulsivity and hyperactivity, higher rates of problem behaviors
9–12 years: Deficits in executive function tasks, increased hyperactivity and inattention, lower academic achievement, higher rates of depressive symptoms and externalizing behaviors
13–16 years: Deficits in attention span and problem-solving skills, lower academic achievement, higher rates of depressive symptoms, earlier and more substance use
18–22 years: Changes in neural activity, higher rates of depressive symptoms, increased risk of psychosis, and higher rates of substance use

Self-study curriculum from the Colorado School of Public Health

Researchers at the Colorado School of Public Health spent months poring over thousands of published articles to create a self-study curriculum for The Tea on THC. See how much you know about why people use high concentration cannabis during pregnancy and parenting, and what it may be doing to their (and the baby’s) mental and physical health.

Lesson 1 - Cannabis, your baby and you

Learn about the THC delivery mechanisms available today, how THC concentrations have grown dramatically, and how cannabis affects both mother and child — with effects potentially lasting a lifetime.

By participating in this lesson, expecting and new parents will learn:

What cannabis is.
Different kinds of cannabis products, including high concentration products.
The impacts of cannabis use on your physical and mental health, as well as on your fetus or child.

Lesson 1

Lesson 2 - Balanced Beginnings: Stress management for expecting and new parents

Learn about the latest scientific insights on stress, develop healthy coping skills, and explore resources to prevent substance use. Equip yourself with the tools to transform challenges into opportunities for growth.

By participating in this lesson, expecting and new parents will be able to:

Understand stress and its influence on parents, fetuses and children.
Build healthy coping skills to manage everyday stress and reduce or limit substance use, including use of high concentration cannabis.
Identify resources for substance use prevention and treatment.

Lesson 2