Abortion and breast cancer risk in seven countries

Abstract

Epidemiologic studies have been inconsistent in suggesting an association between abortion and breast cancer risk. Whether the protection provided by a full-term pregnancy also results from a short-term pregnancy or whether a prematurely terminated pregnancy could increase the risk of breast cancer is unclear. Data from a large, international collaborative study were used to evaluate the association between abortions, whether spontaneous or induced, and breast cancer risk. The data from seven countries included 3,958 breast cancer cases and 11,538 hospital controls with information on abortion history obtained through interviews. Compared with nulliparous women with no abortion (baseline), the odds ratios (OR) and 95 percent confidence intervals (CI) were: for nulliparous women with a history of prior abortion, 0,86 (CI=0.68–1.08); for parous women with no history of abortion, 0.63 (CI=0.57–0.69); for parous women with abortion before first birth, 0.82 (CI=0.69–0.97); and, for parous women with abortion only after first birth, 0.70 (CI=0.63–0.79). When restricting analysis to parous women, those with a history of abortion exhibited an elevated OR suggesting a 29 percent risk increase if the incomplete pregnancy occurred before first birth (CI=1.16–1.36) and an 11 percent risk increase for abortion only after first birth (CI=1.02–1.20) compared with women without such history. The associations observed were stronger among the youngest women. These results do not support a large overall association between abortion and breast cancer risk.

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References

  1. 1.

    Pike MC, Henderson BE, Casagrande JT, Rosario I, Gray GE. Oral contraceptive use and early abortion as risk factors for breast cancer in young women. Br J Cancer 1981; 43: 72–6.

    Google Scholar 

  2. 2.

    Salber EJ, Trichopoulos D, MacMahon B. Lactation and reproductive histories of breast cancer patients in Boston, 1965–66. JNCI 1969; 43: 1013–24.

    Google Scholar 

  3. 3.

    Lowe CR, MacMahon B. Breast cancer and reproductive history of women in South Wales. Lancet 1970; 1(639): 153–7.

    Google Scholar 

  4. 4.

    Ravnihar B, MacMahon B, Lindtner J. Epidemiologic features of breast cancer in Slovenia, 1965–1967. Eur J Cancer 1971; 7: 295–306.

    Google Scholar 

  5. 5.

    Mirra AP, Cole P, MacMahon B. Breast cancer in an area of high parity: São Paulo, Brazil. Cancer Rees 1971; 31: 77–83.

    Google Scholar 

  6. 6.

    Stavraky K, Emmons S. Breast cancer in premenopausal and postmenopausal women. JNCI 1974; 53: 647–54.

    Google Scholar 

  7. 7.

    Toti A, Piffanelli A, Pavanelli T, et al. Possible indication of breast cancer risk through discriminant functions. Cancer 1980; 46: 1280–5.

    Google Scholar 

  8. 8.

    Kelsey JL, Fischer DB, Holford TR, et al. Exogenous estrogens and other factors in the epidemiology of breast cancer. JNCI 1981; 67: 327–33.

    Google Scholar 

  9. 9.

    Brinton LA, Hoover R, Fraumeni JFJr. Reproductive factors in the aetiology of breast cancer. Br J Cancer 1983; 47: 757–62.

    Google Scholar 

  10. 10.

    Le MG, Bachelot A, Doyon F, Kramar A, Hill C. Oral contraceptive use and breast or cervical cancer: preliminary results of a French case-control study. In: Wolff JP, Scott JS, eds. Hormones and Sexual Factors in Human Cancer Aetiology. New York, NY (USA): Elsevier, 1984: 139–47.

    Google Scholar 

  11. 11.

    Levshin VF, Chepurko AD. Reproductive anamnesis and mammary carcinoma (in Russian) Sov Med 1986; 6: 15–21.

    Google Scholar 

  12. 12.

    Rosenberg L, Palmer J, Kaufman DW, Strom BL, Schottenfeld D, Shapiro S. Breast cancer in relation to the occurrence and time of induced and spontaneous abortion. Am J Epidemiol 1988; 127: 981–9.

    Google Scholar 

  13. 13.

    Yuan JM, Yu MC, Ross RK, Gao YT, Henderson B. Risk factors for breast cancer in Chinese women in Shanghai. Cancer Res 1988; 48: 1949–53.

    Google Scholar 

  14. 14.

    Adami HO, Bergstrom R, Lund E, Meirik O. Absence of association between reproductive variables and the risk of breast cancer in young women in Sweden and Norway. Br J Cancer 1990; 62: 122–6.

    Google Scholar 

  15. 15.

    Parazzini F, La Vecchia C. Spontaneous and induced abortions and risk of breast cancer. Int J Cancer 1991; 48: 816–20.

    Google Scholar 

  16. 16.

    Parazzini F, La Vecchia C, Negri E, Franceschi S, Bocciolone L. Menstrual and reproductive factors and breast cancer in women with family history of the disease. Int J Cancer 1992; 51: 677–81.

    Google Scholar 

  17. 17.

    Segi M, Fukushima I, Fujisaki S et al. An epidemiological study on cancer in Japan. GANN 1957; 48(supp): 1–63.

    Google Scholar 

  18. 18.

    Valaoras VG, MacMahon B, Trichopoulos D, Polychronopoulou A. Lactation and reproductive histories of breast cancer patients in greater Athens, 1965–67. Int J Cancer 1969; 4: 350–63.

    Google Scholar 

  19. 19.

    Yuasa S, MacMahon B. Lactation and reproductive histories of breast cancer patients in Tokyo, Japan. Bull WHO 1970; 42: 195–204.

    Google Scholar 

  20. 20.

    Lin TM, Chen KP, MacMahon B. Epidemiologic characteristics of cancer of the breast in Taiwan. Cancer 1971; 27: 1497–504.

    Google Scholar 

  21. 21.

    Soini I. Risk factors of breast cancer in Finland. Int J Epidemiol 1977; 6: 365–73.

    Google Scholar 

  22. 22.

    Choi NW, Howe R, Miller B, et al. An epidemiologic study of breast cancer. Am J Epidemiol 1978; 107: 510–21.

    Google Scholar 

  23. 23.

    Dvoirin VV, Medvedev AB. The role of reproductive history in breast cancer causation (in Russian) In: Methods and Results of Studies of Breast Cancer Epidemiology. Tallinn 1978: 53–6.

  24. 24.

    Hirohata T, Shigematsu T, Nomura AMY, Nomura Y, Horie A, Hirohata I. Occurrence of breast cancer in relation to diet and reproductive history: a case-control study in Fukuoka, Japan. NCI Monographs 1985; 69: 187–90.

    Google Scholar 

  25. 25.

    Ewert M, Duffy SW. Risk of breast cancer in relation to reproductive factors in Denmark. Br J Cancer 1988; 58: 99–104.

    Google Scholar 

  26. 26.

    Howe HL, Senie RT, Bzduch H, Herzfeld P. Early abortion and breast cancer risk among women under age 40. Int J Epidemiol 1989; 18: 300–4.

    Google Scholar 

  27. 27.

    Andrieu N, Clavel F, Gairard B, et al. Familial risk of breast cancer and abortion. Cancer Detect Prev 1994; 18: 51–5.

    Google Scholar 

  28. 28.

    Paffenbarger RS, Kampert JB, Chang HG. Characteristics that predict risk of breast cancer before and after the menopause. Am J Epidemiol 1980; 112: 258–68.

    Google Scholar 

  29. 29.

    Vessey MP, McPherson K, Yeates D, Doll R. Oral contraceptive use and abortion before first term pregnancy in relation to breast cancer risk. Br J Cancer 1982; 45: 327–31.

    Google Scholar 

  30. 30.

    Gandra L, Barros H, Moreira A, Calheires F, Magalhaes N. Factores de risco para o canero da mama: um estudo caso-controlo. A Medica Portuguesa 1993; 6: 129–33.

    Google Scholar 

  31. 31.

    Hajimichael OC, Boyle CA, Meigs JW. Abortion before first livebirth and risk of breast cancer. Br J Cancer 1986; 53: 281–4.

    Google Scholar 

  32. 32.

    Kvåle G, Heuch I, Eide GE. A prospective study of reproductive factors and breast cancer. Am J Epidemiol 1987; 126: 831–41.

    Google Scholar 

  33. 33.

    Lindefors Harris BM, Eklund G, Meirik O, Rutqvist LE, Wiklund K. Risk of cancer of the breast after legal abortion during first trimester: a Swedish register study. Br Med J 1989; 299: 1430–2.

    Google Scholar 

  34. 34.

    Sellers TA, Potter JD, Severson RK, et al. Difficulty becoming pregnant and family history as interactive risk factors for postmenopausal breast cancer: the Iowa Women's Health Study. Cancer Causes Control 1993; 4: 21–8.

    Google Scholar 

  35. 35.

    Janerich DT, Hoff MB. Evidence for a crossover in breast cancer risk factors. Am J Epidemiol 1982; 116: 737–42.

    Google Scholar 

  36. 36.

    Lubin JH, Burns PE, Blot WJ, et al. Risk factors for breast cancer in women in northern Alberta, Canada, as related to age at diagnosis. JNCI 1982; 68: 211–7.

    Google Scholar 

  37. 37.

    Pathak DR, Speizer FE, Willett WC, Rosner B, Lipnick RJ. Parity and breast cancer risk: possible effect on age at diagnosis. Int J Cancer 1986; 37: 21–5.

    Google Scholar 

  38. 38.

    Bruzzi P, Negri E, La Vecchia C, et al. Short term increase in risk of breast cancer after full term pregnancy. Br Med J 1988; 297: 1096–8.

    Google Scholar 

  39. 39.

    Williams EMI, Jones L, Vessey MP, McPherson K. Short term increase in risk of breast cancer associated with full pregnancy. Br Med J 1990; 300: 578–9.

    Google Scholar 

  40. 40.

    Hsieh C-c, Pavia M, Lambe M, et al. Dual effect of parity on breast cancer risk. Eur J Cancer 1994; 30A: 969–73.

    Google Scholar 

  41. 41.

    Lambe M, Hsieh C-c, Trichopoulos D, Ekbom A, Ravia M, Adami HO. Transient increase in the risk of breast cancer after giving birth. N Engl J Med 1994; 331: 5–9.

    Google Scholar 

  42. 42.

    Russo J, Russo IH. Susceptibility of the mammary gland to carcinogenesis. II, Pregnancy interruption as a risk factor in tumor incidence. Am J Pathol 1980; 100: 497–511.

    Google Scholar 

  43. 43.

    Russo J, Tay LK, Russo IH. Differentistion of the mammary gland and susceptibility to carcinogenesis. Breast Cancer Res Treat 1982; 2: 5–73.

    Google Scholar 

  44. 44.

    MacMahon B, Lin TM, Lowe CR, et al. Lactation and cancer of the breast. Bull WHO 1970; 42: 185–94.

    Google Scholar 

  45. 45.

    MacMahon B, Cole P, Lin TM, et al. Age at first birth and breast cancer risk. Bull WHO 1970; 43: 209–21.

    Google Scholar 

  46. 46.

    Trichopoulos D, Hsieh C-c, MacMahon B, et al. Age at any birth and breast cancer risk. Int J Cancer 1983; 31: 701–4.

    Google Scholar 

  47. 47.

    Hsieh C-c, Trichopoulos D, Katsouyanni K, Yuasa S. Age at menarche, age at menopause, height and obesity as risk factors for breast cancer: associations and interactions in an international case-control study. Int J Cancer 1990; 46: 796–800.

    Google Scholar 

  48. 48.

    Hsieh C-c, Trichopoulos D. Breast size, handedness and breast cancer risk. Eur J Cancer 1991; 27: 131–5.

    Google Scholar 

  49. 49.

    Hsieh C-c, Goldman M, Pavia M, et al. Breast cancer risk in mothers of multiple births. Int J Cancer 1993; 54: 81–4.

    Google Scholar 

  50. 50.

    Easton DF, Peto J, Babiker AGAG. Floating absolute risk: an alternative to relative risk in survival and case-control analysis avoiding an arbitrary reference group. Stat Med 1991; 10: 1025–35.

    Google Scholar 

  51. 51.

    MacMahon B. Reproduction and cancer of the breast. Cancer 1993; 71: 3183–8.

    Google Scholar 

  52. 52.

    Russo J, Russo IH. Development of the human mammary gland. In: Neville MC, Daniel C, eds. The Mammary Gland. New York, NY (USA): Plenum Press, 1987: 67–93.

    Google Scholar 

  53. 53.

    Russo J, Rivera R, Russo IH. Influence of age and parity on the development of the human breast. Breast Cancer Res Treat 1992; 23: 211–8.

    Google Scholar 

  54. 54.

    Rosner B, Colditz GA, Willett WC. Reproductive risk factors in a prospective study of breast cancer: the Nurses' Health Study. Am J Epidemiol 1994; 139: 819–35.

    Google Scholar 

  55. 55.

    Willett WC, Stampfer MJ, Colditz GA, Rosner BA, Hennekens CH, Speizer FE. Moderate alcohol consumption and the risk of breast cancer. NEJM 1987; 316: 1174–80.

    Google Scholar 

  56. 56.

    Schatzkin A, Jones DY, Hoover RN, et al. Alcohol consumption and breast cancer in the epidemiologic follow-up study of the first National Health and Nutrition Examination Survey. NEJM 1987; 316: 1169–73.

    Google Scholar 

  57. 57.

    Longnecker MP. Alcohol beverage consumption in relation to risk of breast cancer: meta-analysis and review. Cancer Causes Control 1994; 5: 73–82.

    Google Scholar 

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Additional information

Ms Michels and Drs Hsieh, Trichopoulos, and Willett are with the Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA. Dr Willett is also affiliated with the Department of Nutrition, Harvard School of Public Health, and Channing Laboratory, Department of Medicine, brigham and Women's Hospital and Harvard Medical School, Boston, MA. Address correspondence to Ms Michels, Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA.

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Michels, K.B., Hsieh, Cc., Trichopoulos, D. et al. Abortion and breast cancer risk in seven countries. Cancer Causes Control 6, 75–82 (1995). https://doi.org/10.1007/BF00051683

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Key words

  • Abortion
  • breast cancer
  • international comparison
  • miscarriage
  • pregnancy