title: Oral contraceptives, cigarette smoking and other factors in relation to arthritis.
abstract: The data on oral contraceptive use and arthritis in the Oxford-Family Planning Association contraceptive study have been analysed. For rheumatoid arthritis, the rate of first referral to hospital was 0.33 per 1000 woman-years in those who never used oral contraceptives (27 cases), 0.33 per 1000 woman-years in ex-users of oral contraceptives (29 cases) and 0.44 per 1000 woman-years in current users of oral contraceptives (22 cases). Likewise, there was no important association between oral contraceptive use and other forms of arthritis. An unexpected finding was a strong association between referral to hospital for rheumatoid arthritis and cigarette smoking; the rate in women never smoking was 0.27 per 1000 woman-years (34 cases) and in those smoking 15 or more cigarettes per day was 0.64 per 1000 woman-years (19 cases).
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000139:chemically induced*; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010003:Osteoarthritis / Q000139:chemically induced*; D012017:Referral and Consultation; D012306:Risk; D012907:Smoking
chemical_list: D003276:Contraceptives, Oral