September 2005

Statement Statement compounds in public health terms, even in in even terms, health public in compounds of profile not risk-benefit do overall the IARC evaluate that note to important is It are series. Monographs conclusions IARC the in published Their exposures. and agents of combinations agents, of the variety a by evaluate of posed humans to risks to carcinogenic groups experts convenes international regularly IARC new. is that classification IARC the of updating the only is It the media. in discussed widely and time that at bodies scientific by assessed was and ago is not new, but was several published years The evidence available to this recent review published in Lancet Oncology this month was IARC by review new the of summary A 1). (Group humans” to “carcinogenic to therapy menopausal combined hormonal of classification the changed and COCs of classification the confirmed this review then, new since accumulated evidence to the of basis the carcinogenic On 2B). (Group humans” “possibly menopausal as hormonal therapy combined 1) and (Group humans” to “carcinogenic as 1999 in Monograph IARC an as published and review formulations these on IARC similar by undertaken a of update an was This published in 2006 2006 in published be to Monograph, IARC an be will meeting this of outcome The therapy. menopausal hormonal estrogen-progestogen combined estrogen- progestogen oral combined and contraceptives (COCs) to by risks posed humans carcinogenic the on evidence scientific the a review to experts of convened meeting (IARC) Cancer on Research for Agency International the 2005, June In menopausal treatment contraceptives and combined Carcinogenicity of combined hormonal SpecialResearch,DevelopmentProgramme of Bank UNDP/UNFPA/WHO/World and Research TrainingResearch and (HRP) Humanin Reproduction (2) . At that time, were COCs classified (1) . (3) . . cancers and increase the risk of some some of others. risk the some increase on and effect cancers protective a have that compounds for risk cancer overall of terms the health risks. health the healthy exceed clearly benefits most health the women, for that determined have they and use COC of benefits and risks of balance the assess and COCs of review safety the regularly a They on basis. up-to-date continuous them keeping on and guidelines planning family evidence-based creating on work committees WHO Several are WHO. within teams calculations different by out carried risk-benefit on based higher-dose COC older preparations. to Assessments refer data these of Some ovary). liver), decreasing it in others (endometrium, breast, (cervix, sites some in it increasing of cancer, of risk use the slightly the modifies review, COCs IARC’s in stated As Com on this combined hormonal replacement replacement hormonal combined women this on for cancer breast risk developing increased of an to point results study “The index.html]: news/notes/note02/en/ [http://www.who.int/mediacentre/ valid remains studies, these of publication the of time the at published statement, WHO’s month. per progestogens of days ten less than included regimens combined these an and when cancer endometrial of risk increased regimens combined used who women in cancer an breast of risk shown increased have menopausal studies recent hormonal therapy, to regard With Hormonal menopausal therapy bined oral contraceptives

UNDP • UNFPA • WHO • World Bank Special Programme of Research, Devleopment and Research Training in Human Reproduction

treatment. This reinforces the general importance of breast cancer screening by mammography for all women over 50 years of age, a recommendation endorsed by WHO as proven to reduce breast cancer mortality”.

(1) IARC. IARC monographs on the evaluation of carcinogenic risks to humans, volume 91, combined estrogen-progestogen contraceptives and combined estrogen- progestogen menopausal therapy. Lyon (in press).

(2) IARC. IARC monographs on the evaluation of carcinogenic risks to humans, volume 72, hormonal contraception and post-menopausal hormonal therapy. Lyon (1999).

(3) Cogliano V, Grosse Y, Baan R, Straif K, Secretan B, El Ghissassi F. Carcinogenicity of combined oestrogen-progestagen contraceptives and menopausal treatment. Lancet Oncology 2005; 6:552-553.

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