Marijuana use is on the rise across the United States, and it is the most used drug by people of reproductive age. Not only is marijuana usage increasing, but so are the THC levels in marijuana, and that can impact fertility. At the ENDO 2020, the Endocrine Society’s annual meeting, a group of researchers are presenting the results of an animal study that examined the effect of marijuana use on fertility.
According to Megan Misner, a master’s student in the Department of Biomedical Sciences at the University of Guelph in Canada, says, “Currently, patients seeking infertility treatments are advised against cannabis use, but the scientific evidence backing this statement is weak. This makes it difficult for physicians to properly advise patients undergoing in vitro fertilization."
In the study, the researchers treated female cow eggs with THC in concentrations found in medicinal and recreational doses. The eggs were collected and split into five groups: untreated, control, low THC, mid THC, and high THC. The researchers then measured developmental rates and gene expression. In the eggs treated with high THC levels, the scientists saw a delay in the treated eggs to reach developmental milestones. According to Misner, “This is a key indicator in determining the quality and developmental potential of the egg.”
Exposure to high THC levels decreases the levels of connexins. In high-quality eggs, the level of connexins is also higher. Conversely, low-quality eggs have lower levels of connexins. Says Misner, “This embryo would be less likely to proceed past the first week of development, and thus lead to infertility.”