To date, there have been few appropriate placebo-controlled studies using both subjective and objective parameters to assess the efficacy of
estrogen therapy for the treatment of
urinary incontinence. Further
confusion arises from the heterogeneity of different study protocols. Consequently, the best treatment in terms of type and dose of
estrogen and route of administration is unknown. From these studies, however, there is clear evidence to suggest that recurrent
urinary tract infection can be prevented or even treated by the use of
estrogen therapy. Furthermore, systemic
estrogen replacement appears to alleviate the symptoms of urgency,
urge incontinence, frequency,
nocturia and
dysuria, and low-dose topical
estrogen is effective in the management of
atrophic vaginitis. Although the latter example appears to be free from side-effects, even following prolonged administration, it is unclear whether low-dose
therapy has a sufficient effect on the lower urinary tract to treat
urinary incontinence. There is no conclusive evidence that
estrogen replacement alone is sufficient to cure stress incontinence, but in combination with an
alpha-adrenergic agonist there may be a role for
estrogen therapy in the
conservative management of genuine stress incontinence. On the other hand,
estrogen supplementation definitely improves the quality of life of many postmenopausal women and, therefore, makes them better able to cope with other disabilities. Perhaps the role of
estrogen in the management of postmenopausal urinary disorders is as an adjunct to other methods of treatment such as surgery, physiotherapy and drugs. This is certainly a hypothesis which should be tested.