Dear reader,

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Although the use of menopausal hormone therapy (MHT) has declined after the initial report of data from the women’s health initiative (WHI) in 2002 it is still one of the most frequently prescribed medications. The WHI demonstrated increased risk of breast cancer in current users of combined MHT (EPT) with conjugated estrogens and medroxyprogesterone acetate. Data from the WHI demonstrated a reduced risk for breast cancer in women treated with estrogen only MHT (ET) which was initiated some years after the final menstrual period. Observational studies found an increased breast cancer risk when ET was started at menopausal age and used for many years (>5–10). Thus, the EPT has the greater risk potential. Since progestins differ substantially it was postulated that not all EPT are leading to increased breast cancer risk. Natural progesterone or progesterone derivatives may be less harmful. In recent years, this has been demonstrated by some, but not all observational studies (see article by P. Stute, News and Views section). Although the existing evidence is limited it seems that progesterone as a component in EPT is less harmful. This information extends the discussion and our knowledge on the different risk profile of MHTs. However, we need data from prospective randomized controlled trials to draw clear conclusions. These cannot be performed without substantial financial support which is a major problem in this field. Thus we have to accept that well designed prospective cohort studies offer the best evidence for this clinically very relevant question.

Sincerely,

O. Ortmann

Editor-in-Chief