Medications having unintended effects on pregnancies is not new. Many common treatments must be discontinued if the user becomes pregnant, with some even requiring that anyone who may become pregnant not even start it. This isn’t true for every medication, however, and some are perfectly safe or even specifically formulated for use during pregnancy. If you were to ask how marijuana affects unborn children, or if it causes birth defects, many people likely wouldn’t be able to answer. If you, or someone you know, are looking for affordable Ohio medical marijuana recommendations, the team at DocMJ is here for you! We can easily be reached at our website where we offer an eligibility survey which can tell you if you may instantly pre-qualify!

What Causes Birth Defects?

Birth defects can be caused by many different things and come in many different forms. Birth defects can be physical, mental, or affect the baby’s development later on. There are also more common than most people think, with the CDC estimating that about three percent of births are affected by a major birth defect [1].

There are many factors that can cause, or increase the risk of, birth defects. Genetics are one of the few causes that are considered unpreventable, as most genetic causes are present at conception and therefore cannot be otherwise addressed. Other environmental factors also commonly come into play. These can include the age of the mother, any medications the mother is taking while pregnant, and the overall lifestyle of the parents. Some common causes of birth defects are widely known, while others are more surprising. Drinking alcohol and smoking cigarettes are understood by most people as likely to cause problems in both pregnant women and babies, but other things like stress, pollution, and even certain cosmetic products have been linked to higher rates of birth defects. 

While many babies born with birth defects are able to lead long lives, birth defects are also a large cause of infant mortality in the United States. The CDC believes that up to about twenty percent of all infant deaths are a result of birth defects [2]. Some birth defects also become progressively worse over time, as age and lifestyle choices exacerbate a weakened organ or tissue. 

Marijuana and Birth Defects

Marijuana is a complex medicine. It is composed of over four hundred different chemicals and is consumed and processed in many different ways. Combine those complexities with the intricate body process that are associated with pregnancy, the ethical problems associated with pregnancy-related research, and the recency with which marijuana has been accepted by the larger research community and society overall, you get a drought of direct information on the effects of marijuana on birth defects and pregnant women. Therefore, much of the information we have is either observational or largely theoretical. 

One thing we do know, though, is that pregnant women do use marijuana during pregnancy. In fact, it is the most commonly used illegal drug by pregnant women. Likely because of marijuana’s ability to fight pain and reduce inflammation, some pregnant women have turned to it as an alternative to traditional treatments. Research has found, though, that the chemicals in marijuana can cross the placental barrier, potentially allowing it to affect the fetus [3]. 

Research has also found that the endocannabinoid system has important effects on the body during pregnancy, with levels of specific endocannabinoids fluctuating during each trimester [4]. In the developing fetus, the endocannabinoid system also plays a role in neural differentiation, a point of development where some birth defects begin to form. 

A meta analysis was published in 2016 regarding several important metrics of newborn health after maternal marijuana use. The study found that infants whose mothers used marijuana during pregnancy were at an increased risk of anemia, lower overall birth weights, and were more likely to be sent to intensive care following birth [5]. There are several limitations to the study, though, that the paper points out. Much of the analyzed data was contradicting, and many of the mothers included in the study also used alcohol and tobacco while pregnant, confounding the results. As such, while there is a trend in the data suggesting negative outcomes, more research is needed to determine the effects conclusively. 

In Conclusion

Birth defects are still common in the United States, with about three percent of births being affected. Birth defects can be physical or mental, and may worsen in severity over time. While there is a genetic component, environment and the mother’s lifestyle while pregnant can also increase the risk of the child developing a birth defect. According to the research, marijuana use is linked to an increased risk of developing certain birth defects. While this link is not definitively proven, it is crucial to speak with a certified physician before starting or altering a medical regimen, especially if pregnant. If you think you may benefit from medical marijuana, DocMJ is here for you! Schedule a Telemedicine exam online at or speak with a Patient Care Coordinator at (877) 899.3626. 


[1] Update on Overall Prevalence of Major Birth Defects — Atlanta, Georgia, 1978–2005

[2] NCHS, NVSR, Volume 64, Number 9, August 2015

[3] Marijuana use in pregnancy and lactation: a review of the evidence

[4] Marijuana Use in Pregnancy and While Breastfeeding

[5] Prenatal exposure to cannabis and maternal and child health outcomes: a systematic review and meta-analysis