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 (95% confidence interval 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. 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’ 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 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 Compared with women who did not have a hysterectomy that who younger younger at the hystere ctomy had an adjusted hazard ratio for all cause mortality of 0.82 (95% confidence interval 0.65 to 1.03). Hysterectomy was not associated with a significantly altered risk of mortality from cardiovascular disease or cancer regardless of age. of death in the medium to long term.