If cannabis consumption during pregnancy harmed the child then we would be surrounded by hoards of "The Cannabis Children" because prohibition has not stopped one pregnant mom from smoking or eating cannabis if she wants to. All prohibition has accomplished is to connect pregnant women with the black market.

Remember, the "Crack Babys" of the 80s and 90s? Where are they now that they're young adults? Why aren't they being paraded on Dr Phil? Because that was all a big Drug War lie, there were no crack babys because even crack cocaine didn't harm the foetus. The problem was poverty-stricken, malnorished mothers.