[Primary polyuria in the female. Classification and evolution].

51 adult female patients with unexplained urinary frequency underwent urodynamic assessment and were followed for at least six months. Half of these patients present with unstable bladder which could not be diagnosed clinically, even retrospectively. In 14 out of 16 cases, the instability resolved with an I.V. injection of an anticholinergic drug. The same treatment administered orally "cured" one half of the patients. This proportion was increased to 5 out of 6 when the drug was administered to patients with a positive I.V. test. Symptoms recurred once treatment was stopped. Ten of the 23 patients with a stable bladder improved spontaneously; anticholinergic drugs, when tried, appeared to have no effect. These results demonstrate the importance of diagnosing bladder instability in patients suffering from frequency and urgency.