You clearly don’t understand how studying the impact of harmful things on infants works. You can’t run a typical test because that would be horribly unethical…imagine you’re studying the impact of drinking alcohol during pregnancy. That means you need a test group to drink alcohol and potentially jeopardize their pregnancy and endanger an infant.

This is no different - in fact, much of what is recommended to pregnant women is based on this type of cautious approach. Doctors make the logical conclusion that “If X is bad under this condition, then we shouldn’t expect it to not be bad while pregnant, so don’t do X.”

And directly in that same line of reasoning, here is what is said in the article:

“Studies on the effects of THC in adolescents,” she adds, “have found that kids have long-term issues with cognitive function, executive function, attention issues, depression and anxiety. Until we have more research, we should be cautious and assume that it can affect infants the same way.””

So, I would not dismiss this so readily.