PHOENIX (3TV/CBS 5) -- There is a growing international movement legalizing and decriminalizing marijuana.
In the United States, marijuana is the most popular recreational drug after alcohol and tobacco. As of November 2018, 33 states permit the use of marijuana for medical purposes and 10 states have decriminalized recreational use.
[WATCH: Does marijuana use affect fertility?]
But questions remain.
How safe is marijuana use? Are there long- and short-term side effects that you should worry about?
A recent Boston University study made headlines this month when they reported an association between male marijuana use and female partner miscarriage (regardless of her marijuana use). This prompted a lot of questions about a link between marijuana use and fertility.
Briefly, they reviewed six years of lifestyle and behavioral data from 1,535 heterosexual couples actively trying to conceive to look for lifestyle, dietary, and medical risk factors affecting pregnancy outcomes. They found that the female partners of men who use marijuana one or more times a week were twice as likely to miscarry before eight weeks than men who did not use marijuana at all.
While this result is alarming at first, it must be put in the right context. First, the study found that the two things are associated (male marijuana use and miscarriage) but it was not the type of study that could determine whether marijuana use causes miscarriage. Secondly, we need much more research of the health effects of marijuana. The scientific data on marijuana use is not clear or consistent. Some studies show beneficial effects, (one 2019 study found marijuana users had higher sperm counts than non-users), while others – like this one – points to harms.
Most medical societies are recommending not using marijuana, especially if you are trying to conceive, are pregnant or breastfeeding.