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British Journal of Cancer logoLink to British Journal of Cancer
. 1980 Nov;42(5):651–658. doi: 10.1038/bjc.1980.298

Age at first birth, parity and risk of breast cancer in a Swedish population.

H O Adami, J Hansen, B Jung, A J Rimsten
PMCID: PMC2010566  PMID: 7459205

Abstract

A case-control study was conducted over a period of 11 months in an area containing one-third of the Swedish population. One thousand and one patients participated, constituting 94% of all women newly diagnosed as having breast cancer within the area. They were compared with 1,001 age-matched, non-hospitalized controls without breast cancer, selected by paired sampling from a population register. The risk of breast cancer was slightly, but significantly, related to parity, the standardized relative risk (SRR) being 1.35 for nulliparous women as compared to ever parous. In the different parity groups a risk significantly lower than that for nulliparous women was found only for women with more than 2 children (SRR = 0.59) but the trend with parity was highly significant (P less than 0.001). Age at first birth was not found to be an important risk factor for breast cancer. SRR was lower than for nulliparous women in all groups of women with their first birth before the age of 35 years, but the difference was significant (P less than 0.05) only for those with the first birth between 20 and 24 (SSR = 0.69) and 25 and 29 (SRR = 0.69) years of age. The trend with age at first birth (P less than 0.05) disappeared after stratification for parity, suggesting that it was a confounding factor.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adami H. O., Rimsten A., Stenkvist B., Vegelius J. Reproductive history and risk of breast cancer: a case-control study in an unselected Swedish population. Cancer. 1978 Feb;41(2):747–757. doi: 10.1002/1097-0142(197802)41:2<747::aid-cncr2820410248>3.0.co;2-0. [DOI] [PubMed] [Google Scholar]
  2. Adami H. O., Vegelius J. A method for estimating bias introduced into epidemiological investigations by those who refuse to participate. Ann Clin Res. 1978 Feb;10(1):38–42. [PubMed] [Google Scholar]
  3. Craig T. J., Comstock G. W., Geiser P. B. Epidemiologic comparison of breast cancer patients with early and late onset of malignancy and general population controls. J Natl Cancer Inst. 1974 Dec;53(6):1577–1581. [PubMed] [Google Scholar]
  4. Farewell V. T. The combined effect of breast cancer risk factors. Cancer. 1977 Aug;40(2):931–936. doi: 10.1002/1097-0142(197708)40:2<931::aid-cncr2820400251>3.0.co;2-y. [DOI] [PubMed] [Google Scholar]
  5. Henderson B. E., Powell D., Rosario I., Keys C., Hanisch R., Young M., Casagrande J., Gerkins V., Pike M. C. An epidemiologic study of breast cancer. J Natl Cancer Inst. 1974 Sep;53(3):609–614. doi: 10.1093/jnci/53.3.609. [DOI] [PubMed] [Google Scholar]
  6. Lilienfeld A. M., Coombs J., Bross I. D., Chamberlain A. Marital and reproductive experience in a community-wide epidemiological study of breast cancer. Johns Hopkins Med J. 1975 Apr;136(4):157–162. [PubMed] [Google Scholar]
  7. MANTEL N., HAENSZEL W. Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst. 1959 Apr;22(4):719–748. [PubMed] [Google Scholar]
  8. MacMahon B., Cole P., Brown J. Etiology of human breast cancer: a review. J Natl Cancer Inst. 1973 Jan;50(1):21–42. doi: 10.1093/jnci/50.1.21. [DOI] [PubMed] [Google Scholar]
  9. MacMahon B., Cole P., Lin T. M., Lowe C. R., Mirra A. P., Ravnihar B., Salber E. J., Valaoras V. G., Yuasa S. Age at first birth and breast cancer risk. Bull World Health Organ. 1970;43(2):209–221. [PMC free article] [PubMed] [Google Scholar]
  10. MacMahon B., Lin T. M., Lowe C. R., Mirra A. P., Ravnihar B., Salber E. J., Trichopoulos D., Valaoras V. G., Yuasa S. Lactation and cancer of the breast. A summary of an international study. Bull World Health Organ. 1970;42(2):185–194. [PMC free article] [PubMed] [Google Scholar]
  11. Miettinen O. S. Standardization of risk ratios. Am J Epidemiol. 1972 Dec;96(6):383–388. doi: 10.1093/oxfordjournals.aje.a121470. [DOI] [PubMed] [Google Scholar]
  12. Miettinen O. Estimability and estimation in case-referent studies. Am J Epidemiol. 1976 Feb;103(2):226–235. doi: 10.1093/oxfordjournals.aje.a112220. [DOI] [PubMed] [Google Scholar]
  13. Paymaster J. C. Epidemiology of breast cancer in India. J Natl Cancer Inst. 1972 Apr;48(4):1021–1024. [PubMed] [Google Scholar]
  14. Salber E. J., Trichopulos D., MacMahon B. Lactation and reproductive histories of breast cancer patients in Boston, 1965-66. J Natl Cancer Inst. 1969 Nov;43(5):1013–1024. [PubMed] [Google Scholar]
  15. Sartwell P. E., Arthes F. G., Tonascia J. A. Exogenous hormones, reproductive history, and breast cancer. J Natl Cancer Inst. 1977 Dec;59(6):1589–1592. doi: 10.1093/jnci/59.6.1589. [DOI] [PubMed] [Google Scholar]
  16. Soini I. Risk factors of breast cancer in Finland. Int J Epidemiol. 1977 Dec;6(4):365–373. doi: 10.1093/ije/6.4.365. [DOI] [PubMed] [Google Scholar]
  17. Stavraky K., Emmons S. Breast cancer in premenopausal and postmenopausal women. J Natl Cancer Inst. 1974 Sep;53(3):647–654. doi: 10.1093/jnci/53.3.647. [DOI] [PubMed] [Google Scholar]
  18. Thein-Hlaing, Thein-Maung-Myint Risk factors of breast cancer in Burma. Int J Cancer. 1978 Apr 15;21(4):432–437. doi: 10.1002/ijc.2910210406. [DOI] [PubMed] [Google Scholar]
  19. Wynder E. L., MacCornack F. A., Stellman S. D. The epidemiology of breast cancer in 785 United States Caucasian women. Cancer. 1978 Jun;41(6):2341–2354. doi: 10.1002/1097-0142(197806)41:6<2341::aid-cncr2820410637>3.0.co;2-n. [DOI] [PubMed] [Google Scholar]

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