I am so sorry for your losses @triggerfish227. Seeking answers and going to an RE sounds like the right path. Demand any test you're willing to do and their willing to give you. I hope they can find some answers for you! We are in the same boat. . . no trouble getting pregnant (minus one ovary that I think is a dud). It's the staying pregnant that's got us. I'm trying to stay positive with mine. No blood results or U/S yet so I'm in the dark so far.
I'm so very sorry to hear about your loss and hope your miscarriage is as painless as possible. I really hope some testing can help you find what's keeping you from your bundle of joy.
Good luck!
Re: Failed again! (Loss)
1: BFP 3/14/14; EDD 12/1/14; MMC with HB, D&C 5/8/14
2: BFP 1/31/15; EDD 10/09/15; MMC with HB, Cytotec 3/16/15
6/9/15 Diagnosed MTHFR Compound Heterozygous
3. BFP 8/27/15; EDD 5/08/16