Tysabri and pregnancy

After a few years of TTC we are finally pregnant! My neurologist has known we have been trying but now that I am, he really doesnt have anything reassuring to say about the baby's health while staying on Tysabri infusions. I have been on this for 2 years with no relapses or excertions but if I go completely off I may end up having a rebound effect. So the plan is to stay on tysabri with extended treatment between doses. I feel like a test subject with the medical proffessionals only wanting statistics with no concern of the baby. Have any of you had to go through this?