Nellsbells, after my first miscarriage I was tested for NK cells. Nobody has been able to say exactly what my arthritis is, so it was looked into. I got an inconclusive result. I'd been unable to come off the prednisone for the test, so it would have had some impact on the result.
The level came back at a point that the doctor would have been perfectly happy with a healthy person... but it was higher than he would have liked considering that I was already taking prednisone. At that point in time I was on 10mg (I take all of mine in the morning though, otherwise I don't sleep), and my dosage was increased to 20mg for subsequent frozen embryo transfers. We got through two, and sadly both ended in very early miscarriages.
My gut feeling is that 20mg was too high for me. Prednisone increases insulin resistance and therefore makes the PCOS side of things worse. With this current pregnancy, I stayed on 10mg the whole way through (thinking that it was at least getting my NK cells down to a happy level if I did have an excess of them), and stayed on 10mg... Now I'm at 25 and a half weeks having my insides turned to mash by an ultra-active baby.
The thing with the prednisone is that nobody will be able to tell you if 10mg is enough without having had NK tests done. My PCOS comes with really quite severe insulin resistance and I felt that the increased prednisone may have been taking good care of any NK cells, but it was making another miscarriage cause MUCH worse.
I'm sorry I can't give definite answers. I hate the fact that I can't! All I can do is tell you about my experiences and encourage you to listen to your gut feelings and trust your doctors (hopefully they match, in my case they often didn't). Do you have a family history of auto-immune problems? If not, I'd be inclined to think that the 10mg would be enough for now, but if things don't work out this time, I'd strongly encourage you to get yourself tested for NK cells.
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