If you've been officially diagnosed with celiac or gluten sensitivity, how was it that it was discovered/diagnosed?

My niece was diagnosed last year. After that, my brother's family had a lot of testing done since it's genetic. My brother carries a gene that gives you a 1/200 chance of having celiac, so he went GF along with his daughter.

My sister and I had the blood test. Her's was negative, but mine was inconclusive because my immunoglobulin (sp?) A was low.

Now that I've lost a second pregnancy, I'm wondering if it could be gluten related (or even immunity since my immoglobulin was low?). But before I make that lifestyle change, I'd like to now for sure. And my OBGYN ran the blood test, and wasn't really sure how to interpret the findings. It was a little over their heads.

Did you see an endocrinologist for the final diagnosis? A gastroenterologist? Someone else?

My SIL asked her doctor (not sure what type) about me when I got the low immunoglobulin result, and they said I could either just to go GF and see how I feel or have an intestinal biopsy (that does NOT sound fun!). Or I can take the test my brother took to check my genes and assess my risk, but that's $250...