Who said anything about getting intoxicated? What about having a small glass of wine with dinner?If a pregnant woman cannot deal with a life without drugs, man, think about that before getting pregnant and don't stay intoxicating your child even a little, some things in life need a level of abdication.
You know, it's not like there are only two choices: sobriety or raging drug addict. There's plenty of grey area in between.
The deleterious effects of things like alcohol and weed only harm the fetus cumulatively, i.e. you are doing them daily and in elevated dosages.
Ideally women should be totally sober during pregnancy, but tell that to cultures like the French. Pregnant women drink all the time in France, it's just they have very small amounts and usually it's part of food culture.