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Estradiol (Transdermal)

Estrogens Increase The Risk of Endometrial Cancer

  • There is an increased risk of endometrial cancer in a woman with a uterus who uses unopposed estrogens.
  • Adding a progestin to estrogen therapy has been shown to reduce the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer.
  • Adequate diagnostic measures,  including directed or random endometrial sampling when indicated, should be undertaken to rule out malignancy in postmenopausal women with undiagnosed persistent or recurring abnormal genital bleeding.

      Cardiovascular and Other Risks

  • Estrogens alone should not be used for the prevention of cardiovascular disease.
  • Estrogens Alone WHI Study-Stroke, DVT: The estrogen alone substudy of the Women's Health Initiative (WHI) Study reported increased risks of stroke and deep vein thrombosis in postmenopausal women (50 to 79 years) during 7.1 years of treatment with oral conjugated estrogens (0.625 mg) alone per day relative to placebo (See Package Insert)

      Risk of Probable Dementia

  • Estrogens alone should not be used for the prevention of dementia.
  • WHIMS Data-Dementia: The Women's Health Initiative Memory Study (WHIMS) estrogen alone, anicillary study of WHI, reported an increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 5.2 years of treatment with conjugated estrogens 0.625 mg alone  relative to placebo. It is unknown whether this finding applies to younger postmenopausal women. (See package insert)

      Other General Risk Statements

  • In the absence of comparable data, these risks should be assumed to be similar for other doses of conjugated estrogens and other dosage forms of estrogens.
  • Estrogens with or without progestins should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals for the individual woman.



  • Use lowest possible estrogen dose to control symptoms and discontinue medication as soon as possible
  • If prolonged treatment indicated, reassess patient on at least a semi-annual basis to determine need for continued therapy
  • Close clinical surveillance recommended, monitor for persistent/recurrent abnormal vaginal bleeding.
  • Exposure during pregnancy requires patient appraisal of potential risks.

FDA and Industry Communications

Index to FDA Drug Safety Information

Package Inserts


Updated January 2018