A randomised controlled trial of medroxyprogesterone acetate in mastalgia.

A double-blind crossover study giving 20 mg/day of medroxyprogesterone acetate during the luteal phase was carried out in 26 women with cyclical mastalgia. Symptomatic response to this progestogen supplementation or placebo was assessed objectively by clinical examination and subjectively by linear analogue scales and breast pain charts. No significant relief of pain or tenderness was found on placebo or active treatment, irrespective of treatment order, and breast nodularity was similarly unaltered. No evidence of progesterone deficiency or prolactin abnormality was found. Side-effects were incurred in 11 patients (five on placebo, five on active treatment and one while on both) and were mostly vague premenstrual symptoms. We conclude that the therapeutic response of medroxyprogesterone acetate in cyclical mastalgia is no better than placebo and that progestogen supplementation can no longer be recommended for routine use in the management of breast pain.