It sounds like you've maybe covered all the bases as far as resourcing why this hair loss is occurring, although I don't see one option for this happening in your list....stress. Are you under any type of stress that may be the cause of this hair loss, including the hair loss itself causing you stress? Recent move? New job? Personal loss? You also might want to seek out a second opinion with another Endocrinologist. Many times your lab values may be within normal range, but at a LOW 'NORMAL' RANGE. There are some Endocrinologists out there that will 'tweak' your hormone levels even though they are within the normal range, to a higher normal range to better treat the patient rather than the lab values. Also have your GYN check you for Polycystic Ovarian Syndrome....hope this helps...