They were going to put me on progesterone, but we decided to take a TTC break (it had been almost 2 years). I was tired of Drs & tests & losses & 2 surgeries. They told me if I lost 1 more pregnancy, they were going to send me to a reproductive endocronologist.
I have a friend who's a cardiologist & he's very into healthy diet. DH & I decided we wanted to be more healthy before we started to TTC again. I swapped over to an almost meat free diet (DH was not on board for that

) & started exercising more. I lost about 10 lbs & felt a lot better. I got preggo about 3 months after we stopped TTC. My progesterone levels were perfect & DS was born a healthy 9lbs 13ozs. I have no idea if it was the healthier lifestyle, the decreased stress or a little bit of both. Or honestly, just luck.
My LPs are longer now, but I'm on cycle 5 w/ no luck yet... so beats me. Sorry, I don't have better advice.