Hannah - There are so many reasons for m/c hun, you just need someone who will help you find an answer. When I m/c my first 2 (they were 16wks single, 12wks(twins) as I mentioned I didnt want to go through anymore m/cs before they would look into why. As the hospitals wont do anything unless you have threec m/c in a row. That is why I took it upon myself to find someone who could give me some sort of answer. I was also pg at the time with my DD, which I most probably would have lost if I didnt take things into my own hands. I hope you find someone that will help hun, just dont ever give up on your dream of having that much wanted bub. HUgs