I had a miscarrige at 15 weeks.
My doctor took blood, and ran some tests because we weren't sure why i had a miscarrige... i'm the one doing my iron tests once a week, and taking iron pills+prenatal vitamins+ following a "diet" set forth by my doctor--- i honestly did everything right.

low iron, 14% white blood cell count, and low progesterone...
okay, i get iron and needing white blood cells... but what does progesterone have to do with the pregnancy? and how did somehow... my body not make enough?

I'm sorry to hear of your loss.

I don't have answers myself, but have you checked with the doctor on any of it?