I agree with a lot of the posters here. Imho, you should take their advice. Your wife has to drink water. She should drink plenty of it every day, 8 eight oz glasses of preferably filtered or bottled water. Some of it should be at room temperature, as ice cold water tends to slow peristalsis. She should do light internal cleansing such as a 12 hour juice fast, and take some herbal formulas for constipation such as senna tea. Her previous drug lifestyle has compromised her bodily functions, and it will take some time for it to get back on track, but she can do these things now to get bm's, which are very important, more so since she is pregnant. See a ND. They can prescribe a customized cleansing routine that she can do.
To make water more pleasing, add some lemon and/or 1/2 tsp of sugar.
If things don't start moving soon, let's say a week, I would recommend seeing an MD where he can give her laxatives, or a barium enema. I am not a doctor. My terms or the adminstration of the enema might be wrong, but I think he can help her. Hospitals have a lot of that kind of stuff for emergency unclogging.