Rheumatoid factor (antigammaglobulin) in women: effects of oral contraceptives use of its prevalence.
A total of 14,856 women, including 921 pregnant subjects, were tested for rheumatoid factor; 4,562 were using oral contraceptives at the time of testing. The prevalence of rheumatoid factor increased directly with age. The age-adjusted prevalence of rheumatoid factor was lower in oral contraceptive users than in nonusers but this difference was not statistically significant. Rheumatoid factor remained positive in 39% of subjects undergoing retesting after an average interval of 16 months. Those women with higher titers of rheumatoid factor were more likely to remain positive (81%). Of the women having positive tests, 5.4% were identified as having rheumatoid disease.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis; D001172:Arthritis, Rheumatoid / Q000097:blood; D003276:Contraceptives, Oral / Q000494:pharmacology*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012217:Rheumatoid Factor / Q000032:analysis*; D005719:gamma-Globulins / Q000032:analysis
D000888:Antibodies, Anti-Idiotypic; D003276:Contraceptives, Oral; D005719:gamma-Globulins; D012217:Rheumatoid Factor