Oral contraceptive and IUD use and endometrial cancer: a population-based case-control study in Shanghai, China

Int J Cancer. 2006 Nov 1;119(9):2142-7. doi: 10.1002/ijc.22081.


Oral contraceptive (OC) and intrauterine device (IUD) use have been shown to be protective factors for endometrial cancer in several epidemiological studies; however, few studies have been conducted in Chinese populations. We evaluated the association between OC and IUD use and endometrial cancer risk in a population-based case-control study among Chinese women in Shanghai, China. The study included 1,204 newly diagnosed endometrial cancer cases and 1,212 age frequency-matched healthy controls. Logistic regression models were used to estimate adjusted odds ratios (OR) and their 95% confidence intervals (95% CI). In our study population, 18.5% cases and 24.9% controls reported having ever used OCs with an OR of 0.75 (95% CI, 0.60-0.93), after adjusting for known risk or protective factors for endometrial cancer. The risk of endometrial cancer decreased with long-term use of OCs with the OR for more than 72 months of use being 0.50 (95% CI, 0.30-0.85). The effect of OC use remained 25 or more years after cessation of use; the associated OR was 0.57 (95% CI = 0.42-0.78) as compared to nonusers. Similarly, fewer cases than controls had ever used IUD, with the multivariable adjusted OR being 0.53 (95% CI = 0.43-0.65). A reduction in risk was observed regardless the duration of use or age at first and last use. These results suggest that OC and IUD use may confer long-term protection against endometrial cancer.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Case-Control Studies
  • China / epidemiology
  • Contraceptives, Oral / adverse effects*
  • Endometrial Neoplasms / epidemiology*
  • Female
  • Humans
  • Intrauterine Devices / adverse effects*
  • Middle Aged
  • Risk Factors
  • Smoking
  • Socioeconomic Factors
  • Time Factors


  • Contraceptives, Oral