caz - hope the multivitamins help. If it is a progesterone deficiency though, regular multivitamins won't do much. I've been taking a B-complex vitamin which is supposed to help with the levels, but if they helped me so far, it hasn't been by much. If I get a BFP my doc is willing to give me progesterone supplements just in case since my levels are so low (though its possible my body will pick up the pace if I'm pregnant). Most doctors will offer it to women after 3 miscarriages/chemicals.. at least at my doctor's office.
My friend had 2 chemicals in a row, insisted on treatment/testing and (among other things like clomid to lengthen her LP) they gave her progesterone supplements and her next pregnancy stuck nice and good.