Comments on Dr. Melanie Dreher’s Jamaica Study

Dr. Melanie Dreher’s Jamaica Study

A number of proponents of Dr. Melanie Dreher’s famous Jamaica Study have refuted much of what I’ve said in the pregnancy and perinatal sections of this website. I want to address these issues here.

Dr. Dreher’s work examined a group of Jamaican mothers and their infants during and shortly after pregnancy. Notable for its sensitive, inclusive and holistic design, this study found that the babies of ganja-smoking mothers did better than those of the non-smoking mothers across a number of perinatal testing variables. Moreover, the study indicated that there was a positive correlation between the amounts of cannabis the mothers consumed and testing outcomes.

Dr. Dreher’s Work is Provocative and Important

Like Dr. Dreher, I’ve also spent time with rural people of African ethnicity, including Rastafarians, not in Jamaica but in the jungles of eastern Costa Rica and Nicaragua from 1982-1983. Because of this experience and many others with indigenous healers and shamans all over the world, and being a practitioner and lifetime student of indigenous medicine as well, I feel it’s important to express several points about what is happening with Dr. Dreher’s information.

I agree that Dr. Dreher’s work is provocative and extremely important. I also completely agree with Dr. Dreher that it’s shocking and wrong, though not at all surprising, that her funding got pulled when she published her results. I advocate very strongly that her research continue. I also observe that it’s an unusual social comment on the cannabis community that for as much as it calls for support of Dr. Dreher and her work, very few if any of the billions of dollars in the cannabis industry are funding her further research.

The Jamaica Study is Not Conclusive

Dr. Dreher points out in the Jamaica study that it is far from conclusive. The population in this group was small (33 users and 27 non users), and there’s an abundance of other research that contradicts its findings in significant ways. For example, Lidush Goldschmidt, et al. at University of Pittsburgh Medical Center found that prenatal marijuana use was significantly related to increased hyperactivity, impulsivity, inattention symptoms, increased delinquency and externalizing problems later in life.

The Ottawa Prospective Prenatal Study found developmental issues in infant visual systems, and increased tremors and startle responses among the children of cannabis users. These symptoms disappeared after 1 month and were no longer detectable at 6 and 12 months. However, when they followed up on the cohort at 13-16 years, they found negative effects on memory at age 4, attention at age 6 and visual integration, attention and visual-related aspects of executive function at ages 9 to 12. There were also impacts on tasks that required visual memory, analysis and integration at ages 13-16. Compromises in language development and comprehension pertained throughout.

More recently and most significantly, it has been shown by Psychoyos and Vinod that cannabis use can interfere with the first stages in the formation of the brain of the fetus even earlier than the first signs of pregnancy appear, so these women may be harming their unborn children before they know they are pregnant.

Marijuana and the Pre and Perinatal Period

Just because a study doesn’t praise marijuana’s effects doesn’t mean that it’s prohibitionist propaganda. Marijuana presents a very complicated multidimensional picture at every level of use. Can we hold these seeming contractions at the same time and understand that the effects of marijuana in the pre and perinatal period, just like in any other situation, are complex and case-dependent?

Abusing Dr. Dreher’s Work

It’s also important to consider how this research is being used by those not in the study. A number of people are using the Jamaica study as a justification for taking cannabis irresponsibly during pregnancy and giving it to babies in the post-natal period without sufficient cause. Some of these people are flat-out addicts, fundamentalist fanatics and hate mongers who do much more to harm the cannabis community and its positive goals than they help it. In my opinion they’re abusing Dr. Dreher’s work rather than directing it to the best possible outcomes.

Does this group really understand of the meaning of cross-cultural work such as Dr. Dreher’s and the rich social fabric that it comes from? Can they analyze these data in context and see through to its true import? Can they compare themselves in any realistic way with the population studied by Dr. Dreher?

If we examine the entire context of being a rural Jamaican at the time of the study and compare that with the historical, ethnic, cultural, political, social, economic, spiritual, geographic, climatic, nutritional, educational, relational and psychological realities of the current situations of the members of this group, we’ll all be closer to the truth.

Many of these people are taking marijuana and giving it to their babies not out of medical necessity, but because they are addicts, following addicted logic, patterns of frank denial and illusory dreams. Is marijuana really helping them or their babies to thrive? Who is the judge?

Validating Addiction

An addict will often believe and become a rabid activist for anything that validates his/her addiction. The soundness of an addict’s decisions around her/his drug of choice tend to be inversely proportional to the strength of the addiction. This is no different in the realm of parenting than in any other. Dr. Dreher’s work is about a tapestry of being, not a substance. When you change the context, you change the results.

Marijuana vs. Other Alternatives

My clinical history in this department is thinner than in some others. But I have done extensive pre and perinatal research and clinical time and I’ve worked with a lot of people who have taken a lot of marijuana in every phase of life. I’ve never seen a case where marijuana would have helped a baby more than harm it when compared with other more wholesome alternatives. This doesn’t come from a bias against cannabis. It comes from honest observation and evaluation.

A Right to Choose

I’ve also worked with many people who grew up in situations where they were forced to take marijuana from their earliest moments in life without being given the option to choose whether they wanted it or not. These people have spent their entire lives working through the pain and repercussions of their parents’ decisions. They’ve been left compromised and broken with very few tools to pull a healthy life together for themselves.

Maybe it would be best if a person were allowed to choose to use marijuana or not once s/he is an adult.

In any case, let’s take all of the experimental data into account, including what we learn here in these pages, as we head toward a deeper understanding of the effects of marijuana on pre and perinatal development.

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For extensive details on how to balance and optimize the effects of cannabis using Traditional Chinese Medicine, please refer to

Marijuana Syndromes:

How to Balance and Optimize the Effects of Cannabis With Traditional Chinese Medicine