I use to work at an OB/GYN. The most important thing is if your numbers keep going up. They should double from the last time. If they aren't going up or they are staying the same the baby might not be developing. A nurse at your office should be able to explain what it all means. If they don't I would get a new doctor. I don't know if that answers your question, but I hope things work out for you.
I have not had this issue with any of my pregnancies and I'm sorry you are but keep your faith - I have a friend who had 4 miscarriages and ended up having this same issue. She now has a little girl that just turned 2. Once they found out exactly why her levels were low they were able to do something about it. So good luck!