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The use of noncontraceptive hormones before onset of joint disease was compared between 490 perimenopausal and postmenopausal women with rheumatoid arthritis and a control group of 659 women with soft-tissue rheumatologic disorders and/or osteoarthritis. Both groups were sampled randomly from the attendees of five rheumatologic clinics. A negative association was found between the onset of rheumatoid arthritis and the previous use of noncontraceptive hormones (odds ratio, 0.32; 95% confidence interval, 0.16 to 0.64). This association persisted on univariate and multivariate control of potentially confounding variables and on subgroup analysis. The protective effect of oral contraceptives on the development of rheumatoid arthritis was confirmed.