With cannabis use becoming more socially accepted and legalized in many states, more expectant parents are asking: is smoking weed while pregnant safe? Is marijuana safe while pregnant? When do I have to stop smoking weed while pregnant? Medical experts strongly advise that no amount of cannabis use is considered safe during pregnancy. The answer from major health organizations is clear: there is no known safe amount of cannabis use during pregnancy. Understanding the risks of prenatal cannabis exposure, effects of THC your baby, and safer alternatives is essential for protecting both you and your child.
How THC (Cannabis) Affects Fetal Development
When you use cannabis, the psychoactive ingredient THC (delta-9-tetrahydrocannabinol) crosses the placenta and enters your baby’s bloodstream. Modern cannabis products often contain higher THC levels than in previous decades, increasing the potential risks of marijuana use while pregnant.
Recent 2025 research has strengthened evidence that cannabis use during pregnancy can harm fetal development. Meta-analyses from May 2025 show moderate-certainty evidence linking prenatal cannabis exposure to several adverse outcomes. Even after adjusting for tobacco use, these risks remain significant:
- Low Birth Weight & Fetal Growth Restriction: Babies born to mothers using cannabis may weigh less and show restricted growth in the womb.
- Preterm Birth: Cannabis use may increase the likelihood of delivery before 37 weeks.
- Stillbirth: Some studies suggest a potential higher risk of fetal death after 20 weeks.
- Impaired Lung Development: Biological studies show THC exposure can reduce fetal lung volume and alter gene expression in newborn lungs.
- Neurodevelopmental Issues: Heavy cannabis use during pregnancy can impact memory, attention, problem-solving, and impulse control later in childhood, potentially causing delays in brain development that may persist into adulthood.
- Behavioral Problems: Prenatal cannabis exposure may increase the risk of ADHD, aggression, or other behavioral challenges.
- Long-term Risks: Some research suggests an increased vulnerability to opioid addiction later in life due to effects on the brain’s reward system.
- NICU Admission: Exposed infants are more likely to need care in the neonatal intensive care unit after birth.
Even after adjusting for tobacco use, these risks remain significant CDC: Marijuana and Pregnancy.
The effects of smoking weed or using cannabis while pregnant not only can have severe risks for the developing baby, but the mother as well. Smoking weed while pregnant can affect the mother by harming the lungs, increasing complications, and the risk of addiction.
Secondhand Marijuana Smoke and Pregnancy Risks
Even if you don’t consume cannabis directly, secondhand marijuana smoke can harm your baby and increase the risk of adverse outcomes during or even after pregnancy. Breathing in secondhand smoke introduces harmful chemicals similar to tobacco smoke, contributing to fetal health risks. Marijuana is not safe to inhale while pregnant.
Risks of Cannabis Use for the Pregnant Person
Cannabis use during pregnancy can also affect the health of the expectant parent. Smoking cannabis introduces toxic compounds into your lungs and bloodstream, reducing oxygen supply to your baby. Updated guidance from ACOG 2025 emphasizes:
- Gestational hypertension and preeclampsia
- Placental abruption (placenta separating from the uterus)
- Potential respiratory harm from smoking
The guidance highlights universal screening via patient interviews rather than biological testing to avoid bias, combined with a harm-reduction approach, while still recommending cessation ACOG 2025 Guidance.
Understanding these risks emphasizes why medical professionals advise abstaining from cannabis use during pregnancy. Smoking weed while pregnant is never recommended and comes with many adverse outcomes.
Common Misconceptions About Marijuana Use While Pregnant
Despite legalization and social acceptance, cannabis is not harmless during pregnancy. Key points to know:
- Unregulated Potency: Marijuana products are not FDA-approved, meaning THC levels vary, and products may contain contaminants.
- Symptom Relief Misconception: Some use cannabis to manage nausea, anxiety, or stress, but safer alternatives exist, such as diet changes, exercise, or approved medications.
- No Safe Amount: Even occasional cannabis use during pregnancy carries risks.
Safer Alternatives and Support for Quitting Cannabis
If you are currently using cannabis or plan to become pregnant, discussing it with your healthcare provider is critical. It is recommended to stop smoking weed while pregnant as soon as possible. Quitting cannabis during pregnancy is one of the most important steps you can take to protect your baby’s health. Prenatal care professionals can recommend safe alternatives to cannabis and resources for quitting during pregnancy.
Support resources include:
- Your OB-GYN or maternal-fetal medicine specialist
- SAMHSA National Helpline: 1-800-662-HELP (4357)
The 2025 ACOG guidance encourages supportive and psychobehavioral strategies beyond standard provider discussions:
- Cognitive Behavioral Therapy (CBT) to address habits and triggers
- Motivational Interviewing (MI) to strengthen commitment to cessation
- Structured exercise programs to manage stress and nausea safely
- Supportive home visits or text-messaging interventions for ongoing guidance
FAQ: Smoking Weed While Pregnant
Prenatal cannabis exposure can affect fetal growth and brain development. While research is ongoing, avoiding marijuana during pregnancy is the safest approach.
Stopping immediately and consulting your healthcare provider is recommended. The sooner you cease cannabis use, the lower the potential risks.
No. THC in any form crosses the placenta, so edibles carry similar risks to smoking. Marijuana is not safe while pregnant, no matter the form.
Medical professionals suggest diet adjustments, hydration, prenatal-safe medications, exercise, or mindfulness practices.
Yes. Breathing marijuana smoke exposes the fetus to harmful chemicals, potentially impacting development.
Research suggests that prenatal cannabis exposure may increase risks to fetal development, including low birth weight and neurodevelopmental changes, though evidence for specific structural birth defects is still emerging.
You should stop smoking weed immediately upon discovering you are pregnant, or ideally, even before you start trying to conceive. Major medical organizations, including the American College of Obstetricians and Gynecologists (ACOG) and the Centers for Disease Control and Prevention (CDC), strongly advise against all cannabis use during pregnancy and while breastfeeding due to potential risks to the baby.
Key Takeaways
- Avoid cannabis use before conception, during pregnancy, and while breastfeeding.
- THC crosses the placenta and can affect fetal growth, neurodevelopment, and long-term behavior.
- Secondhand marijuana smoke is harmful.
- Safer alternatives exist for managing pregnancy symptoms; speak with your healthcare provider.
- Marijuana is not safe to use while pregnant
For the latest scientific research, see our in-depth article on cannabis use during pregnancy.
For post-pregnancy, see our article about CBD for postpartum depression.
