@article{3147564,
    title = "Oral contraceptives, reproductive history and risk of colorectal cancer
in the European Prospective Investigation into Cancer and Nutrition",
    author = "Tsilidis, K. K. and Allen, N. E. and Key, T. J. and Bakken, K. and Lund, and E. and Berrino, F. and Fournier, A. and Olsen, A. and Tjonneland, A. and and Overvad, K. and Boutron-Ruault, M-C and Clavel-Chapelon, F. and Byrnes, and G. and Chajes, V. and Rinaldi, S. and Chang-Claude, J. and Kaaks, R. and and Bergmann, M. and Boeing, H. and Koumantaki, Y. and Stasinopoulou, G. and and Trichopoulou, A. and Palli, D. and Tagliabue, G. and Panico, S. and and Tumino, R. and Vineis, P. and Bueno-de-Mesquita, H. B. and van and Duijnhoven, F. J. B. and van Gils, C. H. and Peeters, P. H. M. and and Rodriguez, L. and Gonzalez, C. A. and Sanchez, M-J and Chirlaque, M-D and and Barricarte, A. and Dorronsoro, M. and Borgquist, S. and Manjer, J. and and van Guelpen, B. and Hallmans, G. and Rodwell, S. A. and Khaw, K-T and and Norat, T. and Romaguera, D. and Riboli, E.",
    journal = "British Journal of Cancer",
    year = "2010",
    volume = "103",
    number = "11",
    pages = "1755-1759",
    publisher = "Nature Publishing Group",
    issn = "0007-0920, 1532-1827",
    doi = "10.1038/sj.bjc.6605965",
    keywords = "oral contraceptives; reproductive history; colorectal cancer; cohort
study",
    abstract = "BACKGROUND: Oral contraceptive use and reproductive factors may initiate
long-term changes to the hormonal milieu and thereby, possibly influence
colorectal cancer risk.
METHODS: We examined the association of hormonal and reproductive
factors with risk of colorectal cancer among 337 802 women in the
European Prospective Investigation into Cancer and Nutrition, of whom
1878 developed colorectal cancer.
RESULTS: After stratification for center and age, and adjustment for
body mass index, smoking, diabetes mellitus, physical activity and
alcohol consumption, ever use of oral contraceptives was marginally
inversely associated with colorectal cancer risk (hazard ratio (HR),
0.92; 95% confidence interval (CI), 0.83-1.02), although this
association was stronger among post-menopausal women (HR, 0.84; 95% CI:
0.74-0.95). Duration of oral contraceptive use and reproductive factors,
including age at menarche, age at menopause, type of menopause, ever
having an abortion, parity, age at first full-term pregnancy and
breastfeeding, were not associated with colorectal cancer risk.
CONCLUSION: Our findings provide limited support for a potential inverse
association between oral contraceptives and colorectal cancer risk.
British Journal of Cancer (2010) 103, 1755-1759.
doi:10.1038/sj.bjc.6605965 www.bjcancer.com Published online 2 November
2010 (C) 2010 Cancer Research UK"
}