Abortion history and breast cancer risk: Results from the Shanghai breast cancer study
Article first published online: 2 APR 2001
Copyright © 2001 Wiley-Liss, Inc.
International Journal of Cancer
Volume 92, Issue 6, pages 899–905, 15 June 2001
How to Cite
Sanderson, M., Shu, X.-O., Jin, F., Dai, Q., Wen, W., Hua, Y., Gao, Y.-T. and Zheng, W. (2001), Abortion history and breast cancer risk: Results from the Shanghai breast cancer study. Int. J. Cancer, 92: 899–905. doi: 10.1002/ijc.1263
- Issue published online: 3 MAY 2001
- Article first published online: 2 APR 2001
- Manuscript Accepted: 19 JAN 2001
- Manuscript Revised: 8 JAN 2001
- Manuscript Received: 24 OCT 2000
- National Cancer Institute. Grant Number: R01-CA64227
- breast cancer;
- case-control studies
Studies of the association between induced abortion and breast cancer risk have been inconsistent, perhaps due to underreporting of abortions. Induced abortion is a well-accepted family planning procedure in China, and women who have several induced abortions do not feel stigmatized. The authors used data from a population-based case-control study of breast cancer among women age 25–64 conducted between 1996 and 1998 in urban Shanghai to assess whether a history of and the number of induced abortions were related to breast cancer risk. In-person interviews were completed with 1,459 incident breast cancer cases ascertained through a population-based cancer registry, and 1,556 controls randomly selected from the general population in Shanghai (with respective response rates of 91% and 90%). After adjusting for confounding, there was no relation between ever having had an induced abortion and breast cancer (odds ratio [OR] = 0.9, 95% confidence interval [CI] 0.7–1.2). Women who had 3 or more induced abortions were not at increased risk of premenopausal breast cancer (OR = 0.9, 95% CI 0.6–1.4) or postmenopausal breast cancer (OR = 1.3, 95% CI 0.8–2.3). These results suggest that a history of several induced abortions has little influence on breast cancer risk in Chinese women. © 2001 Wiley-Liss, Inc.