Menstrual and reproductive factors in relation to risk of endometrial cancer in Chinese women

Cancer Causes Control. 2006 Sep;17(7):949-55. doi: 10.1007/s10552-006-0034-6.


Menstrual, reproductive and contraceptive factors have been associated with risk of endometrial cancer in populations where the incidence of this tumor is high. To investigate associations between these factors in a low-risk population with a low prevalence of hormone replacement therapy, we conducted a cohort study among 267,400 women employed in the textile industry in Shanghai, China. Menstrual, reproductive and other factors were ascertained at baseline in 1989-1991, and women were followed for incident endometrial cancer through 31 December 1998 (n = 206). Cox proportional hazards modeling was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Risk of endometrial cancer decreased with increasing age at menarche (p-trend = 0.004). Among menopausal women, risk increased with age at menopause and increasing years of menstruation. Compared to women with one live birth, risk was increased in relation to nulliparity (Hazard ratio = 3.95, 95% CI 1.43-10.86). Risk was decreased with increasing age at first live birth (p-trend = 0.03). There was a decreased risk associated with ever use of an intrauterine device (HR = 0.56, 95% CI 0.35-0.88) and use of oral contraceptives for > or =2 years (HR = 0.50, 95% CI 0.23-1.07). This prospective study confirms findings from previous case-control studies relating menstrual, reproductive, and contraceptive factors and endometrial carcinoma.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • China / epidemiology
  • Cohort Studies
  • Endometrial Neoplasms / epidemiology
  • Endometrial Neoplasms / etiology*
  • Female
  • Humans
  • Incidence
  • Menarche*
  • Menopause
  • Middle Aged
  • Parity*
  • Pregnancy
  • Prospective Studies
  • Risk Factors