Cannabis use is something that many women are afraid to speak about openly. This is especially true when it comes to cannabis use and pregnancy. A study from Kaiser Permanente in Northern California found that more women are using cannabis before and during pregnancy. It looks at the year prior to pregnancy, and early pregnancy, relying on self-reporting from the women about the frequency of their use.

Between 2009 and 2017, the amount of women self-reporting on their cannabis use a year before pregnancy practically doubled. It increased from 6.8 percent to 12.5 percent in eight years. And the amount of use during pregnancy rose from 1.9 percent to 3.4 percent. That number was adjusted for demographics. Additionally, the annual rates of self-reported use daily, weekly and monthly also went up significantly, daily growing most rapidly.

"These findings should alert women's health clinicians to be aware of potential increases in daily and weekly cannabis use among their patients," says study lead author Kelly Young-Wolff, PhD, MPH. She is a research scientist with the Kaiser Permanente Division of Research.

Because they're basing the data on self-reporting by the women, there are still a lot of unknowns. Some women may not admit their cannabis use to their doctors for fear of judgment. The data was drawn from the women's first prenatal visit, which happens around eight weeks gestation. And researchers were unable to know if the usage during early pregnancy was before or after finding out they were pregnant. Some women may use cannabis in the early stages of pregnancy to combat severe morning sickness.

As recreational cannabis use becomes legal in more states, it's important to continue this research. It's important to note that this study uses data from before California legalized recreational use of cannabis. Nancy Goler, M.D., senior author of the study. Goler is an ob-gyn and associate executive director of The Permanente Medical Group explains there is "an urgent need to better understand the effects of prenatal cannabis exposure as cannabis becomes legalized in more states and more widely accepted and used." Which is why this study is so eye opening

Researchers involved in the study admit that there is still a lot to learn about cannabis and pregnancy. While they know that it can certainly contribute to low birth weight, and impair neurodevelopment, everything else needs to be researched further. Especially since there are more ways to use cannabis than just smoking.

"Until such time as we fully understand the specific health risks cannabis poses for pregnant women and their fetuses, we are recommending stopping all cannabis use prior to conceiving and certainly once a woman knows she is pregnant," warns Dr. Goler.

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