Sorry Vicki.........I don't know why I keep losing them. At my first apppointment my RE said she suspected an ovulation problem. She said she thought the egg was no good by the time it was released. But that was just a guess after only talking to me once.
I never did get an answer. My RE didn't seem really interested in helping me get pg I had to ask for clomid and she never offered any further steps. I would have liked to have seen an u/s of my uterus to rule out problematic fibroids since keeping the baby was the problem.
I never did get any answers and I haven't been back to her because we've decided to quit TTC.
Sorry that your sister is going through it too..........it can really mess with you when you get that BFP and then BANG! it's over