Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns. A posterior urethral valve is an obstructing membrane in the posterior male urethra as a result of abnormal "in utero" development. It is the most common cause of bladder outlet obstruction in male newborns. The disorder varies in degree, with mild cases presenting late due to milder symptoms. More severe cases can have renal and respiratory failure from lung underdevelopment as result of low amniotic fluid volumes, requiring intensive care and close monitoring. It occurs in about one in 8000 babies.

Urethral diverticula are often asymptomatic and symptoms that are present tend to be nonspecific. They can co-occur with cancer, in approximately 6-9% of cases, most commonly adenocarcinoma, but also including squamous cell carcinoma and transitional cell carcinoma. Approximately 10% of cases co-occur with kidney stones.

There are 2 types of urethral diverticulums. Congenital and acquired. In infancy usually the urethral diverticulum is congenital but in rare instances acquired urethral diverticulum can be seen in infancy specially following traumatic catheterization.

Common symptoms of urethral diverticulum include incontinence, urinary frequency and urgency, pain during sex, and pain during urination. Other symptoms include pain localized to the urethra or pelvis and frequent urinary tract infection.

When urethral diverticulum becomes severe, a painful mass can sometimes be felt inside the introitus of the vagina, which can discharge pus. If the mass is hard or bleeds, complications like cancer or kidney stones may be present.

Posterior urethral obstruction was first classified by H. H. Young in 1919. The "verumontanum", or mountain ridge, is a distinctive landmark in the prostatic urethra, important in the systemic division of posterior valve disorders:

- Type I - Most common type; due to anterior fusing of the "plicae colliculi", mucosal fins extending from the bottom of the verumontanum distally along the prostatic and membranous urethra

- Type II - Least common variant; vertical or longitudinal folds between the verumontanum and proximal prostatic urethra and bladder neck

- Type III - Less common variant; a disc of tissue distal to verumontanum, also theorized to be a developmental anomaly of congenital urogenital remnants in the bulbar urethra

Dewan has suggested that obstruction in the posterior urethra is more appropriately termed congenital obstructions of the posterior urethral membrane (COPUMs), a concept that has come from an in-depth analysis of the historical papers, and evaluation of patients with a prenatal diagnosis that has facilitated video recording of the uninstrumented obstructed urethra. The congenital obstructive lesions in the bulbar urethra, named Type III Valves by Young in 1919, have been eponymously referred to as Cobb's collar or Moorman's ring. For each of the COPUM (Posterior Urethra) and Cobb's (Bulbar Urethra) lesions, the degree of obstruction can be variable, consistent with a variable expression of the embryopathy. The now nearly one hundred year old nomenclature of posterior urethral valves was based on limited radiology and primitive endoscopy, thus a change COPUM or Cobb's has been appropriate.

The hallmark sign of urethral stricture is a weak urinary stream. Other symptoms include:

- Splaying of the urinary stream

- Urinary frequency

- Urinary urgency

- Straining to urinate

- Pain during urination

- Urinary tract infection

- Prostatitis

- Inability to completely empty the bladder.

Some patients with severe urethral strictures are completely unable to urinate. This is referred to as acute urinary retention, and is a medical emergency. Hydronephrosis and renal failure may also occur.

Most children with vesicoureteral reflux are asymptomatic. Vesicoureteral reflux may be diagnosed as a result of further evaluation of dilation of the kidney or ureters draining urine from the kidney while in utero as well as when a sibling has VUR (though routine testing in either circumstance is controversial). Reflux also increases risk of acute bladder and kidney infections, so testing for reflux may be performed after a child has one or more infections.

In infants, the signs and symptoms of a urinary tract infection may include only fever and lethargy, with poor appetite and sometimes foul-smelling urine, while older children typically present with discomfort or pain with urination and frequent urination.

A urethral diverticulum is a condition where the urethra or the periurethral glands push into the connective tissue layers (fascia) that surround it.

Vesicoureteral reflux (VUR), also known as vesicoureteric reflux, is a condition in which urine flows retrograde, or backward, from the bladder into the ureters/kidneys. Urine normally travels in one direction (forward, or anterograde) from the kidneys to the bladder via the ureters, with a 1-way valve at the vesicoureteral (ureteral-bladder) junction preventing backflow. The valve is formed by oblique tunneling of the distal ureter through the wall of the bladder, creating a short length of ureter (1–2 cm) that can be compressed as the bladder fills. Reflux occurs if the ureter enters the bladder without sufficient tunneling, i.e., too "end-on".

A urethral stricture is a narrowing of the urethra caused by injury, instrumentation, infection and certain non-infectious forms of urethritis.

Urethral meatal stenosis or urethral stricture is a narrowing (stenosis) of the opening of the urethra at the external meatus , thus constricting the opening through which urine leaves the body from the urinary bladder.

Bulbar urethral necrosis is a problem that can occur after a pelvic fracture associated urethral distraction defect (PFUDD).

Patients with erectile dysfunction (ED) and PFUDD or patients with PFUDD and traumatic disruption of the dorsal arteries are susceptible to bulbar urethral necrosis. These patients need tubularized substitution urethroplasty, which is replacement of the bulbar urethra with a various number of tubularized flaps ranging from scrotal skin to sigmoid colon (and others).

The protection provided by the foreskin for the glans penis and meatus has been recognized since 1915. In the absence of the foreskin the meatus is exposed to mechanical and chemical irritation from ammoniacal diaper (nappie) that produces blister formation and ulceration of the urethral opening, which eventually gives rise to meatal stenosis (a narrowing of the opening). Meatal stenosis may also be caused by ischemia resulting from damage to the frenular artery during circumcision.

Obstructive uropathy is a structural or functional hindrance of normal urine flow, sometimes leading to renal dysfunction (obstructive nephropathy).

It is a very broad term, and does not imply a location or cause.

A rectovaginal fistula is a medical condition where there is a fistula or abnormal connection between the rectum and the vagina.

Rectovaginal fistula may be extremely debilitating. If the opening between the rectum and vagina is wide it will allow both flatulence and feces to escape through the vagina, leading to fecal incontinence. There is an association with recurrent urinary and vaginal infections. The fistula may also connect the rectum and urethra, which is called recto-urethral fistula. Either conditions can lead to labial fusion. This type of fistula can cause pediatricians to misdiagnose imperforate anus. The severity of the symptoms will depend on the size of fistula. Most often, it appears after about one week or so after delivery.

Hypospadias is a congenital disorder of the urethra where the urinary opening is not at the usual location on the head of the penis. It is the second-most common birth abnormality of the male reproductive system, affecting about one of every 250 males at birth. In roughly 90% of cases, the opening (meatus) is on or near the head of the penis (glans), referred to as distal hypospadias, while the remainder have proximal hypospadias with a meatus near or within the scrotum. Shiny tissue seen extending from the meatus to the tip of the glans, which would have made the urinary channel, is referred to as the urethral plate.

In most cases, the foreskin is also underdeveloped and does not wrap completely around the penis, leaving the underside of the glans penis uncovered. Also, a downward bending of the penis, commonly referred to as chordee, may occur. This is found in 10% of distal hypospadias and 50% of proximal hypospadias at the time of surgery. The scrotum may be higher than usual to either side of the penis, called penoscrotal transposition, adding to the abnormal overall appearance.

Hypospadias is thought to result from failure of the urinary channel to completely tubularize to the end of the penis; the cause is not known. Most often, it is the only abnormal finding, although in about 10% of cases, hypospadias may be part of a syndrome with multiple abnormalities.

The most common associated defect is an undescended testicle, which has been reported in around 3% of infants with distal hypospadias and 10% of those having proximal hypospadias. The combination of hypospadias and an undescended testicle sometimes indicates a disorder of sexual differentiation, and so additional testing may be recommended. Otherwise no blood tests or X-rays are routinely needed in newborns with hypospadias.

Hypospadias can be a symptom or indication of an intersex condition but the presence of hypospadias alone is not enough to classify as intersex. In most cases, hypospadias is not associated with any condition.

It can be caused by a lesion at any point in the urinary tract.

Causes include urolithiasis, posterior urethral valves and ureteral herniation.

Hypospadias is usually diagnosed in the newborn nursery by the characteristic appearance of the penis. The urinary opening (“meatus”) is lower than normal, and most children have only partial development of the foreskin, lacking the normal covering for the glans on the underside. The abnormal “hooded” foreskin calls attention to the condition. However, not all newborns with partial foreskin development have hypospadias, as some have a normal urinary opening with a hooded foreskin, which is called “chordee without hypospadias”.

Megameatus with intact prepuce variant of hypospadias occurs when the foreskin is normal and the hypospadias is concealed. The condition is discovered during newborn circumcision or later in childhood when the foreskin begins to retract. A newborn with normal-appearing foreskin and a straight penis who is discovered to have hypospadias after a circumcision was started can have circumcision completed without worry for jeopardizing future hypospadias repair. Hypospadias is almost never discovered after a circumcision.

The signs and symptoms of hydronephrosis depend upon whether the obstruction is acute or chronic, partial or complete, unilateral or bilateral. Hydronephrosis that occurs acutely with sudden onset (as caused by a kidney stone) can cause intense pain in the flank area (between the hips and ribs). Historically, this type of pain has been described as "Dietl's crisis". Conversely, hydronephrosis that develops gradually will generally cause either attacks of a dull discomfort or no pain. Nausea and vomiting may also occur. An obstruction that occurs at the urethra or bladder outlet can cause pain and pressure resulting from distension of the bladder. Blocking the flow of urine will commonly result in urinary tract infections which can lead to the development of additional stones, fever, and blood or pus in the urine. If complete obstruction occurs, kidney failure may follow.

Blood tests may show impaired kidney function (elevated urea or creatinine) or electrolyte imbalances such as hyponatremia or hyperchloremic metabolic acidosis. Urinalysis may indicate an elevated pH due to the secondary destruction of nephrons within the affected kidney. Physical examination may detect a palpable abdominal or flank mass caused by the enlarged kidney.

Rectovaginal fistulas are often the result of trauma during childbirth (in which case it is known as obstetric fistula) where improper medical interventions are used, such as episiotomy with forceps/vacuum extraction or in situations where there is inadequate health care, such as in some developing countries. Rectovaginal fistula is said to be known as the leading cause in maternal death in developing countries. Risk factors include prolonged labour, difficult instrumental delivery and paramedian episiotomy. Rates in Eritrea are estimated as high as 350 per 100,000 vaginal births. Fistulas can also develop as a result of physical trauma to either the vagina or anus, including from rape. Women with rectovaginal fistulae are often stigmatized in developing countries, and become outcasts.

Rectovaginal fistula can also be a symptom of various diseases, including infection by lymphogranuloma venereum, or the unintended result of surgery, such as episiotomy or sexual reassignment surgery. They may present as a complication of vaginal surgery, including vaginal hysterectomy. They are a recognized presentation of rectal carcinoma or rarely diverticular disease of the bowel or Crohn's disease. They are seen rarely after radiotherapy treatment for cervical cancer.

Hydronephrosis—literally "water inside the kidney"—refers to distension and dilation of the renal pelvis and calyces, usually caused by urinary retention due to obstruction of the free flow of urine from the kidney. Untreated, it leads to progressive atrophy of the kidney. One or both kidneys may be affected. In cases of hydroureteronephrosis, there is distention of both the ureter and the renal pelvis and calices.

Diverticula are described as being true or false depending upon the layers involved:

- True diverticula involve all layers of the structure, including muscularis propria and adventitia, such as Meckel's diverticulum.

- False diverticula (also known as "pseudodiverticula") do not involve muscular layers or adventitia. False diverticula, in the GI tract for instance, involve only the submucosa and mucosa.

Diverticula may occur in one of the three areas of the esophagus - the pharyngoesophageal, the midesophageal area or the epiphrenic area of esophagus. Zenker's diverticulum is found three times more frequently in men than in women. It occurs posteriorly through the cricopharyngeal muscle in the midline of the neck. Usually seen in people older than 60 years of age.

- Gastric diverticula - "Although usually asymptomatic, they may cause vague epigastric pain. These lesions may be confused radiologically for gastric ulcers or cancers. Endoscopically, they may be confused for paraesophageal hernias."

- Killian-Jamieson diverticulum

- Meckel's diverticulum: a persistent portion of the omphalomesenteric duct present in 2% of the population

- Rokitansky-Aschoff sinuses: in the gallbladder due to chronic cholecystitis

- Traction esophageal diverticulum: due to scarring from mediastinal or pulmonary tuberculosis

- Urethral diverticulum: congenital in males, post-infectious in females

- Zenker's diverticulum: a diverticulum of the mucosa of the pharynx affecting adults

Most of these pathological types of diverticulum are capable of harboring an enterolith. If the enterolith stays in place, it may cause no problems, but a large enterolith expelled from a diverticulum into the lumen can cause obstruction.

A Gartner's duct cyst (sometimes incorrectly referred to as "vaginal inclusion cyst") is a benign vaginal cystic lesion that arises from the Gartner's duct, which is a vestigial remnant of the mesonephric duct (wolffian duct) in females. They are typically small asymptomatic cysts that occur along the lateral walls of the vagina, following the course of the duct. They can present in adolescence with painful menstruation (Dysmenorrhea) or difficulty inserting a tampon. They can also enlarge to substantial proportions and be mistaken for urethral diverticulum or other structures.

There is a small association between Gartner's duct cysts and metanephric urinary anomalies, such as ectopic ureter & ipsilateral renal hypoplasia. Because of this, imaging is recommended before excision.

The pathophysiology of the condition results from neuronal plasticity associated with bladder afferents and motor neurons innervating the external urethral sphincter. People with this condition generally experience daytime and night time wetting, urinary retention, and often have a history of urinary tract and bladder infections. Constipation and encopresis are often associated with this condition.

Despite the similarity of name, an epispadias is not a type of hypospadias, and involves a problem with a different set of embryologic processes.

Women can also have this type of congenital malformation. Epispadias of the female may occur when the urethra develops too far anteriorly, exiting in the clitoris or even more forward. For females, this may not cause difficulty in urination but may cause problems with sexual satisfaction. Frequently, the clitoris is bifurcated at the site of urethral exit, and therefore clitoral sensation is less intense during sexual intercourse due to frequent stimulation during urination. However, with proper stimulation, using either manual or positional techniques, clitoral orgasm is definitely possible.