PREGNANCY, MULTIPLE
PREMENSTRUAL SYNDROME
P
may involve
counselling
or
psychother-
apy,
(See also
conversion disorder,)
pregnancy, multiple The presence of
more than 1 fetus in the uterus, Multi-
ple pregnancy can occur if
2
or more
ova (eggs) are fertilized at the same
time, or if a single fertilized egg divides
early in development,
Twins occur in about 1 in 80 pregnan-
cies, triplets in about
1
in
8
,
000
, and
quadruplets in about 1 in 73,000, Multi-
ple pregnancies are more common in
women who are treated with
fertility
drugs
or if a number of fertilized ova are
implanted during
in vitro fertilization
,
pregnancy tests Tests on urine or blood
performed to determine whether or not
a woman is pregnant, Pregnancy testing
kits that are available from pharmacies
allow testing to be carried out at home,
All of the kits test for the presence of
human chorionic gonadotrophin
(HCG) in
a sample of urine, This hormone is nor-
mally produced only by a developing
placenta, and therefore the tests are
extremely accurate (about 97 per cent
accurate for a positive result and about
80 per cent accurate for a negative
result), even in early pregnancy. Details
for using a test vary with different
brands; but all kits involve dipping a
test stick that has been treated with a
chemical that reacts with HCG into a
sample of urine. Blood tests for detect-
ing pregnancy produce a result from
9-12 days after conception.
PREGNANCY TEST
Result
window
Result
window
Indicator
showing
that test
has
worked
NEGATIVE RESULT
Band
indicator
showing
presence
of HCG
POSITIVE RESULT
HOME PREGNANCY TEST
premature
ejaculation See
ejacula-
tion, disorders of
,
prematurity Birth of a baby before 37
weeks'
gestation,
The premature infant
may not be sufficiently developed to
cope with independent life and needs
special care, About 5-10 per cent of
babies are born prematurely,
Some 40 per cent of premature deliv-
eries occur for no known reason, The
remainder are due to conditions such
as
pre-eclampsia
,
hypertension
,
diabetes
mellitus
, long-standing kidney disease,
and heart disease, Other causes are
antepartum haemorrhage
, intrauterine
infection, or premature rupture of mem-
branes, A common cause is multiple
pregnancy (see
pregnancy, multiple
),
A premature infant is smaller than a
full-term baby, lacks subcutaneous fat,
is covered with downy hair (
lanugo
),
and has very thin skin, The baby's inter-
nal organs are also immature, The
major complication is
respiratory dis-
tress syndrome
, There is increased risk
of brain haemorrhage,
jaundice,
and
hypoglycaemia,
The baby has a limited
ability to suck and maintain body tem-
perature, and is prone to infection, The
earlier a baby is born, the more likely it
is to have such problems,
Premature infants are usually nursed
in a special baby unit that provides
intensive care, The baby is placed in an
incubator,
and may have artificial
venti-
lation
to
assist
breathing,
artificial
feeding through a stomach tube or into
a vein, and treatment with
antibiotic
drugs
and
iron
and
vitamin supplements,
With modern techniques, some infants
survive even if they are born as early as
24 weeks' gestation,
premedication The term
applied to
drugs given, often by injection,
1 -2
hours before an operation to prepare a
person for surgery, Premedication usu-
ally contains a opioid
analgesic drug
and often an
anticholinergic drug,
premenstrual
syndrome The com-
bination of physical and emotional
symptoms that occurs in many women
in the week or so before menstruation,
Premenstrual syndrome (PMS) may be
so severe that work and social relation-
ships are seriously disrupted,
462
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