Estrogen Should be Added to Federal Cancer-Causing Listhttp://articles.mercola.com/sites/articles/archive/2000/12/31/estrogen-cancer-part-two.aspxEstrogen, the hormone used in birth control pills and hormone replacement therapy, should be listed as a known cancer-causing agent, according to the advisers to the National Toxicology Panel (NTP). Maybe, one scientist said, this step might encourageenCommunityServer 2008.5 SP1 (Build: 31106.3070)