Smoking cannabis during pregnancy...?

Okay ladies I just want opinions. I know several people who have smoked while prenant and their babies came out so perfect and so smart. I know several people who didn't smoke and their babies turned out the same way. I'm not going to lie, I have smoked before. I'm just wondering what everyone's opinion is on the topic. I personally believe no drug should be taken while pregnant unless authorized by your doctor. But what if you're on medical and become pregnant? I understand this is a very controversial topic. Some will say yes and some will think you're insane. For the record, I do not smoke now that I am pregnant. I just want to know opinions.