Henderson Katherine DeLellis, Sullivan-Halley Jane, Reynolds Peggy, Horn-Ross Pamela L, Clarke Christina A, Chang Ellen T, Neuhausen Susan, Ursin Giske, Bernstein Leslie
Department of Cancer Etiology, City of Hope Comprehensive Cancer Center, Duarte, CA 91010, USA.
Contraception. 2008 Jun;77(6):391-6. doi: 10.1016/j.contraception.2008.02.004. Epub 2008 Apr 18.
Early studies of incomplete pregnancy and development of breast cancer suggested that induced abortion might increase risk. Several large prospective studies, which eliminate recall bias, did not detect associations, but this relationship continues to be debated.
To further inform this important question, we examined invasive breast cancer as it relates to incomplete pregnancy, including total number of induced abortions, age at first induced abortion and total number of miscarriages among women participating in the ongoing California Teachers Study (CTS) cohort. Incomplete pregnancy was self-reported on the CTS baseline questionnaire in 1995-1996. Incident breast cancers were ascertained in 3324 women through 2004 via linkage with the California Cancer Registry.
Using Cox multivariable regression, we found no statistically significant association between any measure of incomplete pregnancy and breast cancer risk among nulliparous or parous women.
These results provide strong evidence that there is no relationship between incomplete pregnancy and breast cancer risk.
早期关于不完全妊娠与乳腺癌发生的研究表明，人工流产可能会增加患病风险。几项大型前瞻性研究消除了回忆偏倚，但未发现两者之间存在关联，不过这种关系仍存在争议。
为进一步阐明这个重要问题，我们对参与正在进行的加利福尼亚教师研究（CTS）队列的女性中，与不完全妊娠相关的浸润性乳腺癌进行了研究，包括人工流产总数、首次人工流产年龄以及自然流产总数。不完全妊娠情况是通过1995 - 1996年CTS基线调查问卷自我报告的。截至2004年，通过与加利福尼亚癌症登记处的数据链接，在3324名女性中确定了新发乳腺癌病例。
使用Cox多变量回归分析，我们发现未生育或已生育女性中，任何不完全妊娠指标与乳腺癌风险之间均无统计学上的显著关联。
这些结果提供了有力证据，表明不完全妊娠与乳腺癌风险之间不存在关联。
