theres was an article in high times a few years ago about a study between 4 groups of pregnant women. those that drank alcohol during pregnancy, those that smoke cigs, those that smoke bud, and those that did nothing. the results found that babies born from mothers who smoked bud were just as healthy if not more so(higher birth weight and faster development) as the women that did nothing.

also in the article it gave advice about drug testing during pregnancy. basicly it said be upfront with your doctor and if he/she has problem with it go to another doctor.