The effects of the hormonal deficit assume a great relevance because they involve several elements related to urinary incontinence, such as urethral mucosa, the alfa-adrenergics receptors of the urethra, the collagen of the pelvic floor and the peri-urethral vascularization(10,11,12,13).
The collagen tissue participates in the formation of the ligaments and of the sustentation tissues, and of suspension of the pelvic organs and have a close relation with the estrogenic levels. So, depending on the analized organ we may observe different alterations. In the urethra and in the bladder, estrogen replacement in castrated rats increased the quantity of muscular fibers and lowered the total collagen(14,15,16).
Another important estrogenic effect is the modulation of the adrenergics receptors, this means that they increase the number and the sensitivity of these receptors, increasing the sphincterian peri-urethral muscle tone(12,17,18).
The urethral mucosa participates in the continence mechanism, producing a sealing effect, through its coaptation. However, we know that the bladder and urethral mucosa, similar to the vaginal, suffer an extrinsic influence. Reduction of the thickness and change of the type of epithellum with the estrogen deficiency is described. Such facts tend to diminish its sealing effect(19,20).
The vascular peri-urethral net, important element in the maintenance of urinary continence, accounts for a third of urethral pressure. Additionally, the estrogen promotes pronounced enlargement of the blood supply, mainly in the proximal and medium regions of the urethra. Initially, we assessed this repercussion in an experimental model, quantifying the number of periurethral vessels in castrated rats before and during hormonal replacement and after, by dopplervelocitometry of the peri-urethral blood vessels. We noted having a marked decrease in the blood flow and in the number of vessels, and an increase of vascular resistance in post menopause women, which reverted with estrogenic replacement(21,22,23).
Reduction of muscle mass and loss of ligament resistance is described, justifying the appearance of genital prolapse and also contributing to the genesis of urinary incontinence because it increases mobility of the bladder neck.
Urinary complaints generally manifest after other symptoms of the menopause. We distinguish among most frequent, stress urinary incontinence, urgency, polyuria, nycturia, nocturnal enuresis, incomplete bladder emptying and urinary tract infection episodes.
The alterations of bladder sensibility must not be neglected because of atrophy or by aging, it causes considerable discomfort to the patients. Not rarely do we encounter patients with important complaints of dysuria, polyuria, urgency and even urgeincontinence, with a great limitation and terrible suffering. These symptoms may occur from estrogen deficiency, being easily treated by an adequate hormonal replacement.
The detrusor may suffer trabeculation with formation of pseudo diverticulum and the urethra can develop distal fibrosis with eversion of the mucosa, the caruncle.
The subsidiary exams stand out from the urodynamic exam and the ultra sonography of the bladder neck. We must mention also, the importance of a urinary cytology, when there exists complaint of frequency and urgency in the population with an elevated age range.