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Urethra Defects


Ronald Rabinowitz

, MD, University of Rochester Medical Center;

Jimena Cubillos

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised Aug 2022 | Modified Sep 2022
Topic Resources

A Look Inside the Urinary Tract

A Look Inside the Urinary Tract

Types of Birth Defects of the Urethra

There are several types of birth defects of the urethra. The urethra may be

  • Partially blocked

  • In the wrong place

  • Bulging out from its opening (prolapsed urethra)

  • Duplicated (two or more urethras instead of just one)

These defects may

  • Block the flow of urine

  • Cause urine to come out from the wrong location

The Urethra

Partially blocked urethra

Several birth defects partially block the urethra.

In posterior urethral valves, folds of abnormal tissue in the urethra block the flow of urine from the bladder. Posterior urethral valves occur only in boys. The blockage increases the pressure in the bladder and can cause difficulty urinating and a weak urine stream. In more severe forms, the blockage affects the developing fetus. The increased urine pressure from the blockage can interfere with development of the bladder and kidneys. The blockage also may reduce the amount of urine the fetus releases into the amniotic fluid (the fluid that surrounds the fetus in the uterus). If the fetus does not release enough urine into the amniotic fluid, the amount of amniotic fluid is reduced. If there is too little amniotic fluid, problems occur with the development of the fetus's lungs, heart Overview of Heart Defects About one in 100 babies is born with a heart defect. Some are severe, but many are not. Defects may involve abnormal formation of the heart's walls or valves or of the blood vessels that enter... read more , and limbs Missing or Incompletely Formed Limbs Limbs can be missing, deformed, or incompletely developed at birth. Birth defects, also called congenital anomalies, are physical abnormalities that occur before a baby is born. "Congenital"... read more Missing or Incompletely Formed Limbs . Poor lung development can lead to death shortly before or after birth. After birth, affected infants have symptoms of poor bladder drainage or poor kidney function.

A urethral stricture is a narrowing of the urethra that is usually caused by an injury, most commonly a crush injury that occurs when boys fall straddling a hard object. Sometimes urethral stricture is a birth defect or occurs after surgical repair is done to correct a defect of the penis called hypospadias Hypospadias Birth defects of the genitals can involve the penis, scrotum, or testes (testicles) in boys and the vagina and labia in girls. Sometimes the genitals are ambiguous, that is, not clearly female... read more Hypospadias . It is more common among boys.

In urethral meatal stenosis, the outside opening of the urethra (meatus) is narrow and decreases and misdirects the flow of urine. This occurs mostly in boys who previously had surgery on their penis or were circumcised as newborns.

Urethra in the wrong place

The opening of the urethra may be in the wrong place.

In girls, the opening of the urethra may be misplaced between the clitoris and the labia, inside the opening of the vagina, or rarely on the abdomen.

Urethral prolapse

Urethral prolapse occurs in girls. In this disorder, the inner lining of the urethra sticks out through the opening of the urethra. When urethral prolapse occurs, the opening of the urethra looks like a small red and swollen donut. Urethral prolapse typically does not cause symptoms, but the prolapsed tissue may bleed, causing blood spots on the girl's diaper or underwear. This disorder is common among Black girls.

Duplicated urethras (extra urethras)

Rarely, children are born with two or more urethras. Usually only one of them is connected to the bladder, but sometimes they are all connected to the bladder or to each other.

The Ureters, Bladder, and Urethra

Diagnosis of Urethra Defects

  • Physical examination

  • Sometimes voiding cystourethrography

Treatment of Urethra Defects

  • Usually surgical repair

Defects of the urethra that cause symptoms, such as a blockage, usually need to be surgically corrected.

Children who have a blockage in the urethra have surgery to open the blockage as soon as possible. Children whose urethra is abnormal, narrow, or missing may need surgery to correct these defects.

Boys who have posterior urethral valves have surgery when they are diagnosed. Surgery is done to relieve the blockage and prevent further kidney damage. The surgical procedure is usually done with a cystoscope (a small tube with a camera on the end that is inserted into the urethra) to cut the extra tissue that is causing the obstruction. Even after surgery, the bladder may not function normally and boys may need catheterization or additional surgery. Catheterization is draining the bladder by inserting a thin, flexible tube (catheter) through the urethral opening into the bladder.

Boys who have hypospadias may have surgery to repair the defect and correct any other existing defects such as chordee depending on the degree of severity.

Girls who have urethral prolapse may be given a cream that contains estrogen to lessen symptoms. Urethral prolapse usually goes away with time and rarely requires surgery.

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