What to do after two miscarriages in a row?

Jenny • Late 20's. TTC #1 Recovering from 2nd miscarriage at 6-7 weeks.
I'm 29, my husband is 30 and we're TTC baby #1.
First miscarriage was at 5 1/2 weeks a year ago after conceiving naturally. Second one just happened this month after <a href="https://glowing.com/glow-fertility-program">IUI</a> #1 (D&C last Friday). 
We've had the standard round of fertility tests done already - everything came back normal on my end. My husband has a mild motility issue. 
They've ordered another round of RPL tests for clotting disorders etc. and we're waiting for the tissue test results to come back. 
If there's not a clear cause, I'm unsure if we should just do <a href="https://glowing.com/glow-fertility-program">IUI</a> again and hope for the best or move on to <a href="https://glowing.com/glow-fertility-program">IVF</a> w/ genetic testing.
Anyone have a similar experience? 
For those that have had two miscarriages in a row - what did you do next? 
Thanks!
Jen