Introduction

Posterior urethral valves are the commonest congenital obstruction of the lower urinary tract, comprising 10% of antenatally diagnosed uropathies with an incidence of up to 1 in 4000. This figure will rise if non-viable and terminated fetuses are included and as antenatal diagnosis is refined. Equally, there is a group of boys at the other end of the spectrum, whose lesser urethral obstruction produces no early urinary tract dilatation and who present late, even in adulthood with normal renal function and voiding difficulty. The interpretation of this latter group accounts for much of the variation in incidence and the different spectrum of severity found in different series of valve patients.

Posterior urethral obstruction more than any other urinary anomaly, has the capacity to affect the development and function of the whole urinary tract. Our understanding of this problem has evolved over the past decades and has included the identification, classification and treatment of the obstruction; recognition and management of the degrees and types of renal impairment that may be associated with it; the approach to associated vesicoureteric reflux and dilated upper urinary tracts; the function and development of the “valve bladder” (a central issue in our current thoughts about the long-term outcome of posterior urethral valves) and finally the impact on our practice of antenatal diagnosis and the opportunities that it offers not only in the identification but also in the early treatment of posterior urethral valves.

Introduction

Circumcision is the most commonly performed operation in males and is among the oldest, with evidence of its practice in Egyptian mummies – long before Abraham's pact with God introduced ritual circumcision to the Jewish nation in 1713 BC. Ritual circumcision is also practiced among Moslems, Aboriginals, and certain African tribes. Hot, dry climates and poor hygiene predispose to balanitis, so circumcision has conferred some medical benefit to these cultures, a fact that did not escape desert troops in the Second World War and led to an increase in circumcision in Western cultures. On the other hand, its identification with Jewish culture has resulted in an avoidance of circumcision in many central European countries since the War. Currently, it is estimated that one-sixth of the world's population is circumcised.

Religious considerations apart, the variable incidence of circumcision betrays marked differences in cultural and medical attitudes towards the foreskin. Currently, in England the majority of circumcisions are performed for medical reasons (about 21000 annually in children), and it is estimated that 1 in 15 boys are circumcised before their fifteenth birthday. This is significantly less than the 24% rate reported in the 1950s, although more stringent criteria for medical circumcision could undoubtedly effect a further reduction. In Scandinavian countries the rate is the lowest amongst Western cultures in contrast to the United States where routine neonatal circumcision has become the norm and 90% of males are circumcised shortly after birth in some areas.

Introduction

The bladder is an amazing organ with an ability to increase its volume dramatically with little increase in its internal pressure whilst maintaining a securely closed outlet. This enables the bladder to collect urine excreted by the kidneys and store it securely within the body. When the time is appropriate, contraction of the bladder muscular wall causes a rapid rise in its internal pressure and, together with simultaneous relaxation of its outlet, allows urine to be expelled via the urethra. The bladder empties to completion before its outlet closes and its walls relax again to start the next filling cycle.

We start this chapter with a discussion of the anatomy, innervation and control mechanisms of the normal bladder, followed with the evolution of its function from the fetus to the continent adult, the means by which we assess its function and, finally, what is currently known about the effect of sex steroids, the menstrual cycle and pregnancy on the female bladder.

Anatomy

The bladder is an abdominal organ in the fetus and infant that descends as the pelvis deepens towards puberty to become a truly pelvic organ in the mature female (Fig. 7.1). At its apex is the fibrous remnant of the urachus, which ascends in the midline to the umbilicus. Its posterosuperior surface is covered by peritoneum, which is continuous with that of the anterior abdominal wall. As it fills with urine, the bladder rises out of the pelvis between the anterior abdominal wall and its covering peritoneum.