Sorry I can't really offer any advice but this is my third pregnancy and I have never tested positive for antibodies. I am O neg. I just had my 34 week blood test and have tested positive but it is less than 1 (I've forgotten the name but 1 something) so OB says I'll be fine until I deliver in 2 weeks 6 days. The anti-d injections don't always work so my 28 week one must not of worked properly.

Are you seeing an OB?