Long term effects of hysterectomy on mortality: nested cohort study.

OBJECTIVES To investigate the long term risk (mean > 20 years) of death from all causes, cardiovascular disease, and cancer in women who had or had not had a hysterectomy. DESIGN Nested cohort study. SETTING Royal College of General Practitioners' oral contraception study. PARTICIPANTS 7410 women (3705 flagged at the NHS central registries for cancer and death who had a hysterectomy during the oral contraception study and 3705 who were flagged but did not have the operation). MAIN OUTCOME MEASURES Mortality from all causes, cardiovascular disease, and cancer. RESULTS 623 (8.4%) women had died by the end of follow-up (308 in the hysterectomy group and 315 in the non-hysterectomy group). Older women who had had a hysterectomy had a 6% reduced risk of death compared with women of a similar age who did not have the operation (adjusted hazard ratio 0.94, 95% confidence interval 0.75 to 1.18). Compared with young women who did not have a hysterectomy those who were younger at hysterectomy had an adjusted hazard ratio for all cause mortality of 0.82 (0.65 to 1.03). Hysterectomy was not associated with a significantly altered risk of mortality from cardiovascular disease or cancer regardless of age. CONCLUSION Hysterectomy did not increase the risk of death in the medium to long term.