LONG-TERM RISK OF HYSTERECTOMY AMONG 80,007 STERILIZED AND COMPARISONWOMEN AT KAISER PERMANENTE, 1971-1987

To study the long-term risk of hysterectomy after tubal sterilization, the authors analyzed historical hospital discharge data on 39,502 par ous women sterilized during 1971-1984 and 40,505 comparison women matc hed on age, race, parity, and interval since last birth. Sterilized wo men were significantly more likely than were comparison women to under go hysterectomy (relative risk (RR) = 1.35, 95% confidence interval (C I) 1.26-1.44), especially for diagnoses of menstrual dysfunction and p elvic pain (RR = 1.88, 95% CI 1.65-2.13). Higher relative risks were n ot associated with greater tissue-destructive methods of tubal occlusi on. Relative risks were highest for women who were young on the refere nce date (RR = 2.45, 95% CI 1.79-3.36 for women aged 20-24 years), but declined steadily as age increased (RR = 0.96, 95% CI 0.72-1.28 for w omen aged 40-49 years). In all age groups, relative risks were signifi cantly above 1.00 after 7 years of follow-up. Reasons for elevated ris ks may be related to a greater willingness of sterilized women to forg o their uteruses. The emergence of greater risk in all age groups, how ever, prevents the authors from ruling out a possible latent biologic effect of tubal sterilization.