I just thought I would try to be one more non-condescending person that tries to explain my opinion this situation to you. I love marijuana, and I prefer the effects of when I smoke it to the effects of when I eat it, but like you I am looking into getting a vaporizer because my lungs and throat cannot handle smoking. I think it's great that you quit smoking cigarettes while pregnant, btw!
Thus us kind of my reasoning- the reason I get high when I inhale/ingest cannabinoids is because they interact with certain parts of my brain/ CNS. That is the scientific part, but what about what I experience? Things that sometimes happen to me when I get high are: increased heartbeat, lightheadedness, increased appetite, increased sex drive, ability to focus, and it also acts as an anti-depressant and anti-anxiety medication for me. I also use it like you, to treat nausea, aches and pains, mostly migraines and pain from a back injury. Of course it doesn't affect everyone in the exact same ways, but the reason I plan to quit medication with cannabinoids if I ever become pregnant is because I look at it this way: If these chemicals have the ability to affect my fully developed adult brain (and body) in this manner, what could they possibly do to a developing infant?
I know there is no conclusive study as to how exactly marijuana harms prenatal development, if it does in fact at all. But if you just think logically that marijuana could effect your baby on a much larger scale than it affects you because your baby is much smaller and does not have a fully developed immune system, I think a lot people would conclude it's not worth the potential risks, despite lack of evidence of risks and effects. Now, most of my friends with children quit using marijuana when pregnant. However, if they had a pain or anxiety that was severe and couldn't take medication for it, they smoked once or twice during pregnancy, like some pregnant women have just one glass of wine to help themselves sleep at night. The oldest kid I know in this situation is now 13 and he is fine. But that is just my anecdotal evidence, and I fully support you talking to your doctor about it.
Plus, I am not sure where you live but if you live somewhere where marijuana is illegal, you may want to think about it from that standpoint. If there is a risk of getting your child taken away or you getting arrested because of marijuana, I would rather go to a doctor and get legal prescriptions or recommendations for legal natural remedies that are safe during pregnancy. It is not my belief that marijuana should be illegal, but I would rather not have marijuana than get my child taken away or have to otherwise deal with the legal system re: a schedule I drug possession in America, if you do not have a medical license and live in a state that recognizes your permit to possess it.