Hi, I had a similar sort of thing although it doesn't sound as serious as yours.
In my second pg I had heavy blessing at the 8 week mark, I had an ultrasound and baby was fine and all they said was that the bleeding wasn't coming from inside the sac.I had several more bleeds at 26, 34 and 36 and then was induced shortly after that.no reason could ever be found, baby and placenta were perfect.
Sorry I can't help you with any answers.

Good luck x