Cannabis could be risky for women becoming or hoping to become pregnant. New research out today finds evidence that the drug can negatively affect women’s fertility.

Scientists in Canada examined the impacts of cannabis on eggs and embryos from women undergoing in vitro fertilization treatment. They found that greater levels of tetrahydrocannabinol (THC) exposure were linked to several harmful changes, including eggs and embryos with the wrong number of chromosomes. Though it’s unclear exactly how cannabis may affect pregnancy outcomes in the real world, the findings do support current recommendations to avoid its use during pregnancy, the researchers say.

“Collectively, this data presents compelling evidence that cannabis consumption may negatively impact female fertility,” the research

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