Need Advice IUI vs IVF

My husband and I have been struggling with pregnancy loss and unexplained infertility for over 3 years. My fertility doc has run many tests on both of us and they all turn out fine. I began taking Femara and HCG shot last year and got pregnant after 2 cycles, but lost my baby at 12 weeks, 2 days. We started trying again in January, taking Femara and HCG shots each month. I am producing eggs every cycle. I’ve had as many as 4 eggs ready, but every month AF comes. Last month we tried our first IUI. I had 2 1/2 eggs ready, but it still didn’t work. My hubby is 33 and I turn 32 next month. Do we keep trying IUI for a couple more cycles or go ahead and do IVF? It’s so hard when we don’t have any answers as to why I’m not getting pregnant again! Thanks in advance for your advice.