english.prescrire.org > Spotlight > Archives : 2006 > Hot flushes during menopause: dubious benefit of some phytoestrogens and risks for the uterus

Spotlight: Archives

Every month, the subjects in Prescrire’s Spotlight.

2006 : 1 | 30 | 60

Hot flushes during menopause: dubious benefit of some phytoestrogens and risks for the uterus

Phytoestrogens, sold as a treatment for menopausal hot flushes, have not been adequately evaluated. Confirmed risks, especially for the uterus, need to be weighed up against a limited benefit.

Phytoestrogens are plant extracts sold as a treatment for hot flushes. Their effectiveness is low, even dubious: at best they prevent around 2 hot flushes a week.

One clinical trial studied more than 300 women taking soya phytoestrogens over an extended period. The aim was to assess the consequences on the endometrium (internal wall of the uterus).

An abnormal increase in the number of cells (endometrial hyperplasia) was discovered in around 3.8% of the women treated with phytoestrogens for a period of 5 years. Endometrial hyperplasia is generally considered as a precancerous lesion.

Phytoestrogens have not been adequately evaluated, in particular with regard to thromboembolic risks and breast cancer. The latest data confirm that before using phytoestrogens, the associated risks should be weighed against their limited effectiveness in preventing hot flushes.

©Prescrire January 2006

Source: "Phytoestrogènes : hyperplasie de l'endomètre" Rev Prescrire 2006 ; 26 (268) : 26.

- More articles in Prescrire's "Spotlight"...