Effects of a red clover extract (MF11RCE) on endometrium and sex hormones in postmenopausal women

Maturitas. 2006 Aug 20;55(1):76-81. doi: 10.1016/j.maturitas.2006.01.006. Epub 2006 Mar 2.


Objective: To evaluate the effects of a non-prescription red clover extract (MF11 RCE, Melbrosin International, Vienna, Austria) on selected sex hormones and endometrium in postmenopausal women.

Patients and methods: One-hundred and nine postmenopausal women with an age > or =40 years were randomly assigned to one of two groups either two capsules of MF11RCE (80mg isoflavone) per day for a 90 day period, or placebo of equal design. After a 7 day washout period, medication was crossed-over for another 90 days.

Results: Combined evaluation demonstrated that supplementation with MF11RCE (verum), in contrast to placebo, significantly increased plasma testosterone levels and decreased endometrial thickness.

Conclusion: MF11RCE exerts a moderate effect on testosterone levels in postmenopausal women, while estradiol levels remained unchanged. The observed reduction of endometrial thickness provides further support for a safe role for isoflavones in terms of endometrial hyperplasia.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Cross-Over Studies
  • Double-Blind Method
  • Endometrium / drug effects*
  • Endometrium / pathology
  • Female
  • Gonadal Steroid Hormones / blood*
  • Humans
  • Isoflavones / administration & dosage
  • Isoflavones / pharmacology*
  • Isoflavones / therapeutic use
  • Phytotherapy*
  • Plant Extracts / administration & dosage
  • Plant Extracts / pharmacology*
  • Plant Extracts / therapeutic use
  • Postmenopause*
  • Prospective Studies
  • Testosterone / blood
  • Treatment Outcome
  • Trifolium*


  • Gonadal Steroid Hormones
  • Isoflavones
  • Plant Extracts
  • Testosterone