Question for all the ladies TTC.

I have been going back and forth to the OB, my hematologist and the lab for several rounds of blood work to figure out why my body can not hold onto a pregnancy. Tomorrow I go in to check my progesterone levels. Obviously my husband and I have no issue fertilizing an egg but it just wont stay. This is my 2nd miscarriage in 6 months.

My question is, how many of you ladies have found out that it's the progesterone levels in your body that kept causing the losses?