Verdict is still out, but I've contended that the ubiquity of antidepressants is a big contender for cause. Marijuana use is interesting, though.
Many of us alive today were born to mothers who smoked while we were in utero. I don't support it per se, but aside from low birth weight, tobacco use by expectant mothers doesn't appear to be a factor for mental incapacity.
Well, you’re absolutely right about anti-depressants being another possible cause. Those drugs have also exploded in popularity among women of child-bearing-age over the last couple decades. Regarding nicotine, it certainly doesn’t have the psychotropic properties of cannabis or anti-depressants. The cohort of tobacco-smoking mommies circa 1940-80 was absolutely huge. It certainly wasn’t healthy, and there undoubtedly was some fallout from that, but I can’t say that I’ve noticed mental differences between those in-utero nicotine-exposed kids and their nicotine-free counterparts. Not saying that there aren’t any, but I haven’t noticed that among the people I know.
Anything that affects moms cognitive function affects the baby’s brain. Of course.
Marijuana. Alcohol. Antidepressants. Whatever.