Thanks for the response manny. I suppose it is possible to get pregnant naturally despite the low progesterone since it already happened once, but the ob said that my lining is probably to thin for implantation. My level was just 3.7ng/ml at 7 DPO. It took 6 cycles the first time, and I'm already on my 4th cycle since the MMC. Hoping Prometrium helps speed things along. Did it take you long to conceive naturally with low progesterone?