Abstract
The effect of administration of 12.5 micrograms ethinyloestradiol to 10 female patients with active rheumatoid arthritis was investigated in a prospective double blind crossover study. Some improvement during oestrogen treatment was found in 30 m walking time, haemoglobin concentration, and thrombocytosis. Erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) deteriorated in both periods, but less in the oestrogen period. Grip strength improved during both periods. The number of swollen joints decreased, whereas the joint tenderness score increased during the oestrogen period.