Case-Control Study of Cervical Cancer in South African Women


To assess whether the use of injectable progestogen contraceptives (IPCs) and of oral contraceptives influences the risk of cervical cancer (stage Ib or greater).


524 cases of primary invasive cervical cancer (stage Ib or greater) were enrolled from two tertiary care hospitals in Cape Town from among African women and women of mixed racial descent. 1,540 hospital controls were frequency matched to the cases in a ratio of up to 3:1 on age, ethnic group, and area of residence. Controls referred from outlying areas were enrolled from outlying hospitals. Information was collected from the patients by trained nurses on demographic factors, reproductive and contraceptive history, and risk factors for cervical cancer. Blood samples were obtained from all subjects and Pap smears from controls.


Use of IPCs was not associated with the risk of invasive cervical cancer. An unexpected finding was an inverse association between Pap smear and HPV infection.

Investigators and Study Staff

Samuel Shapiro M.B., Principal Investigator
Slone Epidemiology Center

Lynn Rosenberg, Sc.D., Co-Investigator
Slone Epidemiology Center

Margaret Hoffman, M.B., Principal Investigator
University of Cape Town

Study Details

Source of Funding:

National Cancer Institute

Study Period:

1998 to 2002


  • Cooper D, Hoffman M, Carrara H, Rosenberg L, Kelly J, Stander I, Denny L, Williamson A, Shapiro S.  Determinants of sexual activity and its relation to cervical cancer risk among South African women.  BMC Public Health 2007;7:341.
  • Hoffman M, Shapiro S, Rosenberg L, Kelly JP, Cooper DD, Carrara H, Williamson AL, Denny LE, du Toit G, Allen BR, Stander IA. Limited Pap screening associated with reduced risk of cervical cancer in South Africa. Int J Epidemiol 2003;32:573-7.
  • Shapiro S, Rosenberg L, Hoffman M, Kelly JP, Cooper DD, Carrara H, Williamson AL, Denny LE, du Toit G, Allan BR, Stander IA. Risk of invasive cancer of the cervix in relation to the use of injectable progestogen contraceptives and combined estrogen/progestogen contraceptives (South Africa). Cancer Causes Control 2003;14:485-95.
  • Hoffman M, Rosenberg L, Shapiro S. Case-control studies of screening should carry a health warning: response [letter to the editor]. Int J Epidemiol 2003;32:1112.
  • Shapiro S, Carrara H, Allan BR, Hoffman M, Rosenberg L, Kelly JP, Cooper DD, Williamson A. Hypothesis: the act of taking a Papanicolaou smear reduces the prevalence of human papillomavirus infection: a potential impact on the risk of cervical cancer. Cancer Causes Control 2003;14:953-7.