threatening circumstance that typically occurs
when a tube partially reanastomoses but the fertil-
ized egg cannot pass through the tube to the
uterus and instead begins to grow in the fallopian
tube or the abdominal cavity.
Outlook and Lifestyle Modifications
Tubal ligation has no effect on a woman’s LIBIDO
(sex drive), and in fact may increase a woman’s
interest in sexual activity because she no longer
worries about unintended pregnancy. However,
tubal ligation does not protect against SEXUALLY
TRANSMITTED DISEASES(STDS) or HIV/AIDS.
The intent of tubal ligation is to establish per-
manent infertility (sterility), and a woman should
consider tubal ligation to be permanent though it
is sometimes possible to reverse a tubal ligation
through a second surgery. The operation to
reverse tubal ligation is usually major abdominal
open surgery; its success depends on multiple fac-
tors, including the woman’s current age and the
age at which she had the tubal ligation and the
skill of the surgeon.
See also CONCEPTION; FAMILY PLANNING; SEXUALLY
TRANSMITTED DISEASE(STD) PREVENTION; VASECTOMY.
Turner’s syndrome A spontaneous (nonheredi-
tary) chromosomal disorder in which there are
abnormalities of the X CHROMOSOME, theSEX CHRO-
MOSOMEthat establishes female gender, resulting
in various anatomic and physiologic anomalies.
These abnormalities may include only a single X
chromosome (X chromosome deletion) instead of
the normal pair of X chromosomes, or one com-
plete and one fragmented or partial X chromo-
some. As well, the pattern may be mosaic, with
some cells in the body carrying the normal paired
X chromosome complement and others carrying
the abnormality. Turner’s syndrome affects only
females.
Though symptoms of Turner’s syndrome vary
depending on the severity of the chromosomal
abnormality, characteristic traits include very short
stature and loss or lack of ovarian function. An
unusually short neck with webbed SKIN, and a
broad, shield-shaped chest may be prominent at
birth to suggest the presence of Turner’s syndrome
though often the diagnosis comes later in child-
hood or early ADOLESCENCEwhen SECONDARY SEXUAL
CHARACTERISTICS fail to develop. GENETIC TESTING
(KARYOTYPE) confirms the diagnosis. Anomalies of
the HEART(coarctation of the AORTA) and KIDNEYS
(HORSESHOE KIDNEY) are also common. As adults,
women who have Turner’s syndrome have
increased risk for type 2 DIABETES, HYPOTHYROIDISM
(underactive THYROID GLANDfunction), HYPERTEN-
SION(high BLOOD PRESSURE), and OSTEOPOROSIS.
HORMONE THERAPYwith ESTROGENSand progestin
from PUBERTY through midlife (to the age
MENOPAUSEwould normally occur, around 50) is
the standard course of treatment for Turner’s syn-
drome. This treatment causes relatively normal
development of secondary sexual characteristics
and sometimes of ovarian function to produce
hormones, though the OVARIES do not produce
normal OVA. In mosaic Turner’s syndrome, the
woman’s ovaries may function until early adult-
hood. ASSISTED REPRODUCTIVE TECHNOLOGY (ART)
techniques can make PREGNANCYpossible. There
are no measures to prevent Turner’s syndrome.
See also CHROMOSOMAL DISORDERS; GENETIC DISOR-
DERS; KLINEFELTER’S SYNDROME; MOSAICISM.348 The Reproductive System