I think its harmless when used properly under a doctor's care. That is EXACTLY why I told her to speak to her RE only a doctor can tell her if its safe for her. I would NEVER suggest anyone take medication while trying to get pregnant or stay pregnant without consulting there doctor. Honestly "I" think it is harmless in most cases when used with the permission of a doctor. Aspirin has many side effects and it is a mediction. Lots of great information pros and cons are out there so patients can share the information and their concerns pros and cons with their doctors. I am so glad I took it, I was given permission without any testing being done to see if it would help. So that's why I think its harmless because I had 2 doctors tell me it WOULD not HURT to use it. My re and OB.