Less obvious reasons for miscarriage

TW: mention of LC

We’ve had three miscarriages in a row and all stopped growth between 11-12 weeks. We’ve done the gamut of fertility testing, all POC testing of losses has been normal, blood tests, endometrial biopsy, sperm analysis, extensive genetic screenings for both partners, karyotype tests for both partners, HSG, HyCoSy, etc.

At this point, I’m wondering if it’s possible there’s a reason like high blood pressure or an auto-immune issue (I’m asymptomatic if yes). Has anyone found anything related to this as the cause of their loss(es)?

TW: LC

I do have a LC who I had before these three losses, and he was an uncomplicated pregnancy, but I did have high blood pressure at times during end of pregnancy and postpartum that quickly resolved, but wondering if something like this could be causing my mc.