You are very welcome,Masha.
Since her hormones are perfect, she would need a CT scan of abdomen and other blood work to rule out any systemic illness or a subtle chronic infection, which usually does not give any symptoms and is detectable only by the further blood work. Following would be advised (some of them may have been done) for the evaluation of the cause;
1) Thyroid-stimulating hormone (TSH), prolactin, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) measurements
2) testosterone, dehydroepiandrosterone sulfate (DHEAS), androstenedione, and 17-OH progesterone
3) erythrocyte sedimentation rate (ESR), liver function tests, blood urea nitrogen (BUN) determination, creatinine determination, and urinalysis.
4) Magnetic resonance imaging can detect hypothalamic/pituitary lesions.
5) Progesterone challenge test.
These tests would point the cause and direction for the treatment.
It is privilege assisting you.