When I got pregnant I was on Imuran. I stopped a bit in, personal choice, but really the doctors all reassured me it was safe to be on for pregnancy and such. My little guy is 16 months now and perfectly happy and healthy.
Even breast feeding is a bit split, some say good, some say no...but still, talk to your doctors and find out what they personally think. Alot of women here have been on practically all the meds it seems and had happy healthy babies.
Remember best is always to stay on some sort of med and take care of yourself first and foremost cause an unhealthy flaring up mom is worse then any med that keeps up healthy and controlled basically.
29 year old Crohns patient of 10 years. Currently on Imuran and Vitamin B12 injections.