Due to ethical concerns regard to the results from the WHI study

In order to evaluate the potential effects of estrogen treatment in postmenopausal women with fibromyalgia, the investigators used quantitative sensory tests before and after eight weeks of estrogen treatment as compared with placebo treatment.

Fibromyalgia is a condition that preferentially affects women. Sex hormones, and in particular estrogens, have been shown to affect pain processing and pain sensitivity, and estrogen deficit has been considered a potential promoting factor for fibromyalgia. However, the effects of estrogen treatment in patients suffering from fibromyalgia have not been studied. Twenty-nine postmenopausal women were randomized to either eight weeks of treatment with transdermal 17β-estradiol (50 ug daily) or placebo according to a double-blind protocol. A self-estimation of pain, a set of quantitative sensory tests measuring thresholds to temperature, thermal pain, cold pain and pressure pain, and a cold pressor test were performed at three occasions: before treatment, after eight weeks of treatment, and twenty weeks after cessation of treatment.

Inclusion Criteria:

• Between 49-60 years
• Body mass index (BMI) of < 30
• Met the ACR-90 criteria for the diagnosis of fibromyalgia
• Postmenopausal state since at least six months
• Not been using any hormonal treatments for the past three months
• Had normal mammography screenings

Exclusion Criteria:

• Using psychotropic drugs or having a history of thromboembolism
• Diabetes mellitus, polyneuropathy, chronic liver disease,
• Alcohol or substance abuse, hemoglobinopathy,
• Endometrial adenomatous hyperplasia, or malignancy.
• Presence of untreated hypertension (>160/95).
• Undiagnosed vaginal bleedings