I haven't used progesterone for ttc but use it to help with my cycles (ovarian cysts, nausea, vomitting PMS etc) Pm if you want the details, I get mine on line. I think it has 5mg progesterone which is one of the highest available over the counter but I'm not 100% sure.

For your LP try taking 100mg of B6 it help increase my lp from 9 days to a pos HPT.

All the best