Article Text

Download PDFPDF

Oestrogen plus progestogen increased risk of breast cancer in postmenopausal women

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

 QUESTION: In postmenopausal women, does oestrogen plus progestogen hormone therapy (HT) increase the risk of abnormal mammographic results and diagnoses of breast cancer?


Randomised (allocation concealed*), blinded (clinicians, participants, data collectors, outcome assessors, and monitoring committee),* placebo controlled trial with a mean 5.6 year follow up (Women’s Health Initiative [WHI]).


40 US clinical centres.


16 608 postmenopausal women who were 50–79 years of age (mean age 63.3 y). Exclusion criteria were previous hysterectomy, breast cancer, or probable survival <3 years. Follow up data were available for 15 931 women (95.9%).


Women were allocated to 1 daily tablet of conjugated equine oestrogen, 0.625 mg, and medroxyprogesterone acetate, 2.5 mg (n=8506), or placebo (n=8102).

Main outcome measures

Incidence of breast cancer (total, invasive, and in situ) and abnormal mammogram results.

Main results

Analysis was by intention to treat. Women …

View Full Text