When my wife was pregnant we read a lot of books on child development and such. What we learned is fetus development is a super complex process. There's a lot that can go wrong and what seems minor can have major consequences later on. From what I read I wouldn't advise even eating or vaporizing. You don't smoke alchohol but that is known to be bad for a developing fetus. Remember, if it is affecting your brain its affecting the babies too.

My wife is pretty straight and doesn't smoke or anything but she quit doing everything else. No New Years champagne, no more Starbuck's (the hardest), no sushi(could have parasites), etc, etc. Personnally I though she went a bit overboard but she was only doing what she felt would be best for the baby. Did it really make a difference? Not sure, but what what I do know is that even though she popped out 7 weeks early our daughter is super healthy and has never had any problems at all. She's not even two but understands both English and Chinese, and knows all of the letters in the alphabet. I really don't know many kids her age to compare with but I'm told this is pretty good. Maybe she wouldn't have done so good if my wife had smoked, or eaten, pot during her pregnancy.

Bottom line, why take chances? It's only nine months anyway.