A new study on the impact of marijuana on fish eggs should make pregnant mothers think twice before using cannabis.
The study, which was conducted by a group of researchers led by Decan Ali at the University of Alberta - placed groups of zebrafish eggs in water with various concentration levels of two prominent compounds found in cannabis (THC and CBD) before moving them back to uncontaminated water. They found that the exposed fish eggs had lower rates of hatching and survival. In fact, despite CBD's accepted medical applications, the eggs exposed to high levels of CBD actually had the lowest rate of survival.
Ali admits that these results are not directly transferable to human embryos, but he believes the findings are strong enough that people should consider the potential risks of consuming cannabis during pregnancy.
"I hesitate to translate it directly to humans. However, the proteins that we are looking at, the receptors for these compounds, the way that our bodies work, are very, very similar," Ali told The Star Edmonton. "We use concentrations for these compounds that we believe are physiologically relevant given what’s been measured in human blood plasma after smoking marijuana."
The fish exposed to either THC or CBD had reduced heart rates and slower communication between motor neurons and muscle fibers. Some also suffered from malformations such as cardiac edema and curvature of the back and trunk.
Cannabis "does have clear uses for medicinal purposes," Ali added, but people should still exercise caution in pregnancy.
"I think if you are thinking of becoming pregnant, maybe just take a step back and just rethink your use and consumption of these compounds during the time of pregnancy, in a very similar way that you would for alcohol."
Ali plans to continue to examine the fish as the progress through adulthood and to monitor potential health risks in their offspring. So smoking cannabis to battle morning sickness is still not a good idea.