Mahue-Giangreco Maya, Ursin Giske, Sullivan-Halley Jane, Bernstein Leslie
Department of Preventive Medicine and Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA.
Cancer Epidemiol Biomarkers Prev. 2003 Mar;12(3):209-14.
Early studies of breast cancer raised substantial concern regarding risk associated with induced abortion and miscarriage. Literature reviews suggest that study findings depend heavily on the comparison group and that the use of parous women as a reference group for nulliparous women may artificially inflate risk. To examine the individual effects of induced abortion and miscarriage on breast cancer risk of parous and nulliparous women, 744 patients < or =40 years of age and diagnosed from 1983-1988 were matched by parity, age, and race with controls living in the same neighborhood in Los Angeles County. In-person interviews were conducted to obtain a detailed reproductive history. Risk estimates were obtained by conditional logistic regression using nulligravid women as the reference group for nulliparous women with a history of incomplete pregnancy and parous women with no incomplete pregnancies as the reference group for parous women with a history of incomplete pregnancy. Breast cancer risk of parous women was unrelated to a history of miscarriage or induced abortion. Breast cancer risk was reduced among nulliparous women with a history of induced abortion relative to nulligravid women, although the risk estimate was imprecise. Risk declined as the number of induced abortions increased (P = 0.04). Our results do not support the hypothesis that induced abortion or miscarriage increase the breast cancer risk of young women.
早期关于乳腺癌的研究引发了人们对人工流产和自然流产相关风险的高度关注。文献综述表明，研究结果在很大程度上取决于对照组，并且将经产妇作为未生育妇女的参照组可能会人为地夸大风险。为了研究人工流产和自然流产对经产妇和未生育妇女患乳腺癌风险的个体影响，选取了744名年龄小于或等于40岁且于1983年至1988年期间确诊的患者，按照产次、年龄和种族与居住在洛杉矶县同一社区的对照组进行匹配。通过面对面访谈获取详细的生育史。风险估计通过条件逻辑回归获得，将未孕妇女作为有不完全妊娠史的未生育妇女的参照组，将无不完全妊娠史的经产妇作为有不完全妊娠史的经产妇的参照组。经产妇患乳腺癌的风险与自然流产或人工流产史无关。有过人工流产史的未生育妇女相对于未孕妇女，其患乳腺癌的风险有所降低，尽管风险估计并不精确。随着人工流产次数的增加，风险降低（P = 0.04）。我们的研究结果不支持人工流产或自然流产会增加年轻女性患乳腺癌风险这一假设。
