I had the exact same thing when TTC#2. I would get pregnant ever couple of cycles but couldn't get them to stick for the life of me. Some would "stick" longer than others due to using progesterone supplements which, in my case, really only seemed to delay the bleeding. I managed to stay pregnant with my last pregnancy using Welcome Womb. I don't know if it was the herbs or just finally my time to have a sticky pregnancy but whenever I hear similar stories to mine I have to share my experience. Feel free to check out my blog (
here) or in my siggy. There is a page that describes my history in a bit more detail along with more info about the herbs.
I am so sorry for your losses. It is a hard road to travel. (((hugs)))