口服避孕药的妇女患乳癌的危险性增高,这一问题引起很多争论。Meirik博士及其同事报告了瑞典和挪威全国病例及对照的联合调查研究结果,发现口服避孕药在12年以上时,患乳癌危险性高2倍;随着服药时间的持续,危险性有增高的趋势;同时,在初次足月妊娠前口服避孕药8年以上者患乳癌危险性也增加。这一新近而人数相当多的调查研究(422例,年龄在45岁以下)会怎样影响我们对这一问题的看法和判断呢? 口服避孕药和乳癌的早期研究(包括曾患乳癌的各年龄妇女)未提供证据说明口服避孕 Women with oral contraceptives are at increased risk of breast cancer, a problem that has caused much controversy. Dr. Meirik and colleagues report the results of a joint national and case-control study of Sweden and Norway and found that oral contraceptives are 2-fold more likely to be breast-cancer-specific than 12 years of age and have been associated with an increased risk as time goes by Trend; the same time, before the first full-term pregnancy oral contraceptives more than 8 years also increased risk of breast cancer. How does this new but relatively large number of studies (422 cases, under the age of 45) affect our perceptions and judgments on this issue? Early studies of oral contraceptives and breast cancer (including those with breast cancer at various ages Women) did not provide evidence of oral contraception