Well, I'm in my first trimester and I have a urinary track infection, and a doctor at a hospital prescribed me Nitrofurantoin 100 mg , 4 times a day, of course the side effects are worse in me, I guess because of my pregnancy, but I need to know if it's really safe for my baby, I'm not having any problems in my pregnancy, and I don't have any spotting, thanks God. But I had a miscarriage before and I'm very concerned about any pills doctors make me take.