alter the environment within the UTERUSsuch that
a fertilized ovum (egg) cannot implant. The
woman must take emergency contraception no
later than 72 hours after unprotected SEXUAL INTER-
COURSE.
See also CONCEPTION; FAMILY PLANNING; FERTILITY;
INFERTILITY; OVA; SEXUAL HEALTH; SEXUALLY TRANSMIT-
TED DISEASE(STD) PREVENTION; SPERM.
cryptorchidism Undescended testicle. The TESTI-
CLESform within the abdominal cavity early in
fetal development and normally descend through
the inguinal canal at the floor of the pelvis into
the SCROTUMduring the third trimester of PREG-
NANCY. In some boys the testicle may sponta-
neously descend during the first year of life; after
one year of age, however, this is unlikely. Numer-
ous factors contribute to cryptorchidism, key
among them being genetic and hormonal influ-
ences.
Treatment to bring the testicle outside the body
is essential to preserve FERTILITYand because a tes-
ticle retained within the abdominal cavity has a
high risk for TESTICULAR CANCER.
Treatment options are hormonal therapy, in
which GONADOTROPIN-RELEASING HORMONE (GNRH)
administration may stimulate the testicle to
descend on its own, and surgery (ORCHIOPEXY) to
shift the testicle from its abdominal position into
the scrotum. Orchiopexy is the more common
therapeutic route. Surgery sometimes involves
procedures to repair related structures such as the
arteries and veins that supply the testicle and the
VAS DEFERENS, the tubular structure that transports
SPERMfrom the testicle. Bilateral cryptorchism, in
which both testicles are undescended, often
results in sterility (permanent inability to father a
child) because normal body temperature destroys
the ability of the testicle to produce sperm.
Even after treatment the risk for testicular can-
cer remains higher than normal; boys and men
who have had cryptorchidism should perform
monthly TESTICULAR SELF-EXAMINATION. Most men
who had successful treatment for cryptorchidism
early in childhood have full fertility. Cryptor-
chidism does not affect sexual function.
See also FERTILITY; HYPOGONADISM; HYPOSPADIAS;
SURGERY BENEFIT AND RISK ASSESSMENT.cryptorchidism 267