"Menopause and fibromyalgia have many overlapping symptoms such as depression, anxiety, sleep disorders, and vasomotor symptoms (hot flashes and night sweats). Fibromyalgia symptoms tend to worsen during menopause, but research shows that estrogen and progesterone replacement therapy is not that beneficial to FM sufferers. One study showed that hormone replacement therapy may actually worsen FM symptoms. As described above, lower estrogen levels can predispose patients to pain. Changes in estrogen levels in the blood are accompanied by changes in a variety of neurotransmitters, particularly serotonin and substance P. Substance P is a neurotransmitter and is elevated in the cerebrospinal fluid of FM patients. Serotonin is a neurotransmitter which suppresses substance P. Low levels of serotonin are seen in FM patients as well as in patients with anxiety and depression." from Change of Life by Dr. Aysun Alagoz. Well, that makes me reconsider whether or not I want to take progesterone therapy, especially long term. Of course, I'm taking it to shrink a cyst. So I see that as a temporary solution. With side benefits of extra energy and fewer hot flashes.