I too have MTHFR. I never thought of it as a horrible thing (as some of the other responses)...just as something I have to deal with.
I had two second tri-mester miscarriages. I developed a blood clot during my first pregnancy. That is how we figured out that I had MTHFR.
After the two miscarriages, I "put myself" in the high-risk area for my third pregnancy. I went to Dr. Silver, the head of maternal fetal medicine at Evanston Northwestern Hospital. I live in Island Lake, so it was a HAUL for every appointment; however worth every mile. I have a healthy 2 yr old little girl!
I take folic acid, a baby aspirin, a B-complex (B6 and B12) vitamins AND I gave myself shots of Lovenox throughout my pregnancy twice a day (and I am scared to death of needles).
I would get a 2nd opinion on the Lovenox (blood thinner) for your pregnancy. I found that the regular OB GYNs meant well; however they just weren't specialized enough to know the right course of action. I found out (during my successful pregnancy) that I was taking too much blood thinner in my 2nd pregnancy. It is not surprising that it represented itself as placenta previa because of that. I think the words I remember was the dosage that you were taking was for a mack truck! Again, I don't fault that dr., they just weren't specialized enough. They were working with my hematologist and just didn't know enough.
Since you had multiple miscarriages, I would suggest Dr. Silver - he and his group are BEYOND AMAZING! They continually discussed my care throughout the pregnancy as a total staff, talking about the best course of action right through to Maggie's delivery (for instance, do we take her off of Lovenox and put her on Heparin because Lovenox stays in your system for a while, etc.)
I would and will go back to them in a heartbeat. I had multiple issues (39 years old, overweight, hypothyroidism, MTHFR, blood clot first pregnancy and water broke, second pregnancy presented itself more as placenta previa)...lots for them to navigate through...and there wasn't one day that I didn't have confidence in my care.
Good luck and I pray that you will be posting the good news in no time!
J.