Hypospadias and Epispadias
Hypospadias and Epispadias
Hypospadias is a congenital defect, primarily of males, in which the urethra opens on the underside (ventrum) of the penis. It is one of the most common congenital abnormalities in the United States, occurring in about one of every 125 live male births. The corresponding defect in females is an opening of the urethra into the vagina and is rare.
Epispadias (also called bladder exstrophy) is a congenital defect of males in which the urethra opens on the upper surface (dorsum) of the penis. The corresponding defect in females is a fissure in the upper wall of the urethra and is quite rare.
In a male, the external opening of the urinary tract (external meatus) is normally located at the tip of the penis. In a female, it is normally located between the clitoris and the vagina.
In males with hypospadias, the urethra opens on the inferior surface or underside of the penis. In females with hypospadias, the urethra opens into the cavity of the vagina.
In males with epispadias, the urethra opens on the superior surface or upper side of the penis. In females with epispadias, there is a crack or fissure in the wall of the urethra and out of the body through an opening in the skin above the clitoris.
During the embryological development of males, a groove of tissue folds inward and then fuses to form a tube that becomes the urethra. Hypospadias occurs when the tube does not form or does not fuse completely. Epispadias is due to a defect in the tissue that folds inward to form the urethra.
During the development of a female, similar processes occur to form the urethra. The problem usually
is insufficient length of the tube that becomes the urethra. As a result, the urethra opens in an abnormal location, resulting in a hypospadias. Occasionally, fissures form in the bladder. These may extend to the surface of the abdomen and fuse with the adjacent skin. This most often is identified as a defect in the bladder although it is technically an epispadias.
Hypospadias in males generally occur alone. Female hypospadias may be associated with abnormalities of the genital tract, since the urinary and genital tracts are formed in the same embryonic process.
Because it represents incomplete development of the penis, some experts think that insufficient male hormone may be responsible for hypospadias.
In males, the incidence of hypospadias is approximately one per 250 to 300 live births. Epispadias is much less common, having an incidence of about one per 100,000 live male births.
In females, hypospadias is much less common than in males. It appears about once in every 500,000 live female births. Epispadias is even rarer. Reliable estimates of the prevalence of epispadias in females are not available. Epispadias in females is often diagnosed and recorded as a bladder anomaly.
Causes and symptoms
Hypospadias and epispadias are congenital defects of the urinary tract. This means they occur during intrauterine development. There is no genetic basis for the defects. Specific causes for hypospadias are not known. This means that blood relatives do not have increased chances of developing them. Reports have shown some rise in prevalence of hypospadias among offspring of mothers who work in certain occupations where they may be exposed to chemicals that disrupt the endocrine system. However, a large trial ending in 2003 showed that aside from a slight increased risk among women who were hairdressers from 1992–1996, there is no evidence that maternal occupation or certain chemical exposure increases risk of hypospadias. The role of chemicals in the development of the defect remains uncertain.
Concern was once raised that use of the antihistamine loratadine (Claritin) early in pregnancy might cause hypospadias. However, a national clinical trial revealed in 2004 that there was no link between the drug and risk of second- or third-degree hypospadias.
Hypospadias usually is not associated with other defects of the penis or urethra. In males, it can occur at any site along the underside of the penis. In females, the urethra exits the body in an abnormal location. This usually is due to inadequate length of the urethra.
Epispadias is associated with bladder abnormalities. In females, the front wall of the bladder does not fuse or close. The bladder fissure may extend to the external abdominal wall. In such a rare case, the front of the pelvis also is widely separated. In males, the bladder fissure extends into the urethra and simply becomes an opening somewhere along the upper surface of the penis.
Hypospadias is associated with difficulty in assigning gender to babies. This occurs when gender is not obvious at birth because of deformities in the sex organs.
Male external urinary tract defects are discovered at birth during the first detailed examination of the newborn. Female urethral defects may not be discovered for some time due to the difficulty in viewing the infant vagina.
Surgery is the treatment of choice for both hypospadias and epispadias. All surgical repairs should be undertaken early and completed without delay. This minimizes psychological trauma.
In males with hypospadias, one surgery usually is sufficient to repair the defect. With more complicated hypospadias (more than one abnormally situated urethral opening), multiple surgeries may be required. In females with hypospadias, surgical repair technically is more complicated but can usually be completed in a brief interval of time.
Repairing an epispadias is more difficult. In males, this may involve other structures in the penis. Males should not be circumcised since the foreskin often is needed for the repair. Unfortunately, choices may be required that affect the ability to inseminate a female partner. Reproduction requires that the urethral meatus be close to the tip of the penis. Cosmetic appearance and ability to urinate (urinary continence) usually are the primary goals. Surgery for these defects is successful 70 to 80% of the time. Modern treatment of complete male epispadias allows for an excellent genital appearance and achievement of urinary continence.
In females, repair of epispadias may require multiple surgical procedures. Urinary continence and cosmetic appearance are the usual primary considerations. Urinary continence usually is achieved although cosmetic appearance may be somewhat compromised. Fertility is not usually affected. Repair rates that are similar or better than those for males usually can be achieved for females.
Hypospadias in both males and females is more of a nuisance and hindrance to reproduction than a threat to health. If surgery is not an option, the condition may be allowed to persist. This usually leads to an increased risk of infections in the lower urinary tract.
With adequate surgical repair, most males with simple hypospadias can lead normal lives with a penis that appears and functions in a normal manner. This includes fathering children. Females with simple hypospadias also have normal lives, including conceiving and bearing children.
The prognosis for epispadias depends on the extent of the defect. Most males with relatively minor epispadias lead normal lives, including fathering children. As the extent of the defect increases, surgical reconstruction generally is acceptable. However, many of these men are unable to conceive children. Most epispadias in females can be surgically repaired. The chances of residual disfigurement increase as the extent of the epispadias increases. Fertility in females is not generally affected by epispadias.
In hypospadias, the urethra opens along the penile shaft rather than at the penile tip.
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Bladder — This is the organ that stores urine after it flows out of the kidneys and through the ureters.
Circumcision — The surgical removal of the foreskin of the penis.
Continence — Normal function of the urinary bladder and urethra, allowing fluid flow during urination and completely stopping flow at other times.
External meatus — The external opening through which urine and seminal fluid (in males only) leave the body.
Genital tract — The organs involved in reproduction. In a male, they include the penis, testicles, prostate and various tubular structures to transport seminal fluid and sperm. In a female, they include the clitoris, vagina, cervix, uterus, fallopian tubes and ovaries.
Urethra — The tubular portion of the urinary tract connecting the bladder and external meatus through which urine passes. In males, seminal fluid and sperm also pass through the urethra.
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