Schlesselman J J, Stadel B V, Murray P, Lai S
Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda 20814.
JAMA. 1988 Mar 25;259(12):1828-33.
A long-term effect of oral contraceptives (OCs) on breast cancer risk has been suggested as an explanation for some studies' failure to detect an association between OCs and breast cancer. To address this latency hypothesis, we analyzed data on 4714 case subjects and 4540 control subjects from the population-based Cancer and Steroid Hormone Study. No support was evident for a latent effect of OCs on breast cancer risk through age 54 years: among parous women who had cumulated more than six years of OC use before their first term pregnancy, the risk of breast cancer, relative to nonusers before first term pregnancy, was 0.6 at zero to four years after first term pregnancy (95% confidence interval [Cl], 0.2 to 1.8), 0.7 at five to nine years (95% Cl, 0.3 to 1.7), and 1.1 at ten to 14 years (95% Cl, 0.3 to 3.9). Among nulliparous women with more than six years of OC use in total, the relative risk of breast cancer, by interval from last use of OCs, was 1.3 at zero to four years (95% Cl, 0.8 to 2.0), 1.1 at five to nine years (95% Cl, 0.5 to 2.0), and 0.6 at ten to 14 years (95% Cl, 0.1 to 3.7).
口服避孕药（OCs）对乳腺癌风险的长期影响被认为是一些研究未能检测到OCs与乳腺癌之间关联的一种解释。为了验证这一潜伏期假说，我们分析了基于人群的癌症与类固醇激素研究中4714例病例受试者和4540例对照受试者的数据。在54岁之前，未发现OCs对乳腺癌风险有潜在影响的明显证据：在首次足月妊娠前累计使用OCs超过6年的经产妇中，相对于首次足月妊娠前未使用者，首次足月妊娠后0至4年患乳腺癌的风险为0.6（95%置信区间[Cl]，0.2至1.8），5至9年为0.7（95%Cl，0.3至1.7），10至14年为1.1（95%Cl，0.3至3.9）。在总共使用OCs超过6年的未生育妇女中，根据距上次使用OCs的时间间隔，患乳腺癌的相对风险在0至4年为1.3（95%Cl，0.8至2.0），5至9年为1.1（95%Cl，0.5至2.0），10至14年为0.6（95%Cl，0.1至3.7）。
