A wide range of medical conditions can cause female hair loss. Besides treatments for cancer, female hair loss may be due to various autoimmune disorders, such as psoriasis or seborrheic dermatitis. Pregnancy can cause hormonal changes in the body that result in hair loss, as can anemia and thyroid disorders. Polycystic Ovary Syndrome (PCOS), extreme stress or trauma, and menopause may also be the cause of female hair loss.