Cryptorchidism - Terminology

Cryptorchidism is a medical term referring to absence from the scrotum of one or both testes. This usually represents failure of the testis to move, to "descend," during fetal development from an abdominal position, through the inguinal canal, into the ipsilateral scrotum. About 3% of full-term infant boys are born with at least one undescended testis, making cryptorchidism the most common birth defect of male genitalia. A testis absent from the normal scrotal position can be: found anywhere along the "path ...

Including:

• Cryptorchidism - Terminology
• Cryptorchidism - Normal fetal testicular development and descent
• Cryptorchidism - Causes of cryptorchidism
• Cryptorchidism - Inheritance and recurrence risk of cryptorchidism
• Cryptorchidism - Associations
• Cryptorchidism - Diagnostic evaluation
• Cryptorchidism - Management of cryptorchidism
• Cryptorchidism - Later fertility
• Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia - Cryptorchidism

The testes begin as an immigration of primordial germ cells into testicular cords along the genital ridge in the abdomen of the early embryo. The interaction of several male genes organizes this developing gonad into a testis rather than an ovary by the second month of gestation. During the 3rd to 5th months, the cells in the testes differentiate into testosterone-producing Leydig cells, and anti-müllerian hormone-producing Sertoli cells. The germ cells in this environment become fetal spermatogonia. Male external genitalia during the 3rd and 4t ...

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Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Normal fetal testicular development and descent

Many men who were born with undescended testes have reduced fertility, even after orchiopexy in infancy. The reduction with unilateral cryptorchidism is subtle, with a reported infertility rate of about 10%, compared with about 6% reported by the same study for the general population of adult men. The fertility reduction after orchiopexy for bilateral cryptorchidism is more marked, about 38%, or 6 times that of the general population. The basis for the universal recommendation for early surgery is research showing degeneration of sper ...

See also:

Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Later fertility

The primary management of cryptorchidism is surgery, called orchiopexy. It is usually performed in infancy, if inguinal testes have not descended after 4-6 months, often by a pediatric urologist or pediatric surgeon, but in many communities still by a general urologist or surgeon. When the undescended testis is in the inguinal canal, hormonal therapy is sometimes attempted and occasionally successful. The most commonly used hormone therapy is human chorionic gonadotropin. A series of hCG injections (10 injections over 5 weeks is commo ...

See also:

Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Management of cryptorchidism

The most common diagnostic dilemma in otherwise normal boys is distinguishing a retractile testis from a testis that will not/cannot descend spontaneously into the scrotum. Retractile testes are more common than truly undescended testes and do not need to be operated on. In normal males, as the cremaster muscle relaxes or contracts, the testis moves lower or higher ("retracts") in the scrotum. This cremasteric reflex is much more active in infant boys than older men. A retractile testis high in the scrotum can be difficult to distinguish fro ...

See also:

Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Diagnostic evaluation

In most full-term infant boys with cryptorchidism but no other genital abnormalities, a cause cannot be found, making this a common, sporadic, unexplained birth defect. Although severely premature infants can be born before descent of testes, there is a strong association of cryptorchidism with low birthweight due to either prematurity or intrauterine growth retardation. In these infants there is usually no evidence of ho ...

See also:

Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Causes of cryptorchidism

A small percentage of cases of isolated cryptorchidism are familial. It has been reported that about 4% of fathers and 6-10% of brothers of affected boys have also had cryptorchidism. Few specific genes associated with isolated cryptorchidism have been identified. In contrast, many of the genes causing some of the intersex conditions associated with androgen or AMH deficiency or insensitivity have been ident ...

See also:

Cryptorchidism, Cryptorchidism - Terminology, Cryptorchidism - Normal fetal testicular development and descent, Cryptorchidism - Causes of cryptorchidism, Cryptorchidism - Inheritance and recurrence risk of cryptorchidism, Cryptorchidism - Associations, Cryptorchidism - Diagnostic evaluation, Cryptorchidism - Management of cryptorchidism, Cryptorchidism - Later fertility, Cryptorchidism - Later cancer risk

Read more here: » Cryptorchidism: Encyclopedia II - Cryptorchidism - Inheritance and recurrence risk of cryptorchidism