Br Med J (Clin Res Ed). 1985 Mar 30;290(6473):961-5. doi: 10.1136/bmj.290.6473.961.
A multicentre, hospital based case-control study is being conducted under the auspices of the World Health Organisation to determine whether steroid contraceptives alter the risk of gynaecological, breast, and hepatic neoplasms. Preliminary results, largely from developing countries, on the relation between combined oral contraceptives and invasive cervical carcinoma showed a relative risk of 1.19 (95% confidence interval 0.99-1.44) in women who had ever used oral contraceptives. The risk increased with duration of use, giving a relative risk of 1.53 after five years. This finding supports a causal interpretation, but it could also be due to incomplete control for confounding sexual variables and other sources of bias.
在世界卫生组织的支持下,正在开展一项以医院为基础的多中心病例对照研究,以确定甾体类避孕药是否会改变患妇科、乳腺和肝脏肿瘤的风险。主要来自发展中国家的关于复方口服避孕药与浸润性宫颈癌之间关系的初步结果显示,曾经使用过口服避孕药的女性的相对风险为1.19(95%置信区间0.99 - 1.44)。风险随使用时间增加,使用五年后的相对风险为1.53。这一发现支持因果关系的解释,但也可能是由于对混杂的性变量和其他偏倚来源控制不完全所致。