INFORMATION ABOUT ULTRASOUND
Pregnan is one of big event in woman life, that's why we have to take care
of this pregnancy as good as we can. Starting our food with a lot of nutrient,
have a good rest, and periodically visit the doctor. Also always keep watch
our pregnancy with a machine name ultrasonografi (USG).
What is ultrasound?
Ultrasound uses sound waves at frequencies higher than the human ear can hear.
The doctor or technician runs the ultrasound transmitter across your abdomen
aided by a greasy substance that improves sound conduction. These sound waves
bounce back off your baby much like sonar waves locating a submarine. These
echoes are detected by a receiver, and then a computer translates the sound
into a picture of baby on a screen. The "Doptone" device used for
detecting your baby's heartbeat also uses ultrasound; the echoes are translated
into the "swish-thump" you hear every month at your checkup. Other
terms that refer to ultrasound include scan, sonogram, doppler (the physics
term for the relationship between sound and the distance it travels), echo,
and electronic fetal monitoring.
Why and when is it used?
Ultrasound gives your doctor vital information and allows parents to "see"
their baby on a TV screen. By eight weeks the image resembles a lima bean with
a pulse; by fifteen weeks the ultrasound image can show baby's major organs;
by the 20th week, the ultrasound pictures confirm the presence or absence of
a penis, so the sex of your baby is apparent (though sometimes this is subject
to misinterpretation). Ultrasound yields information that could influence how
your pregnancy is managed and improve its outcome. (If you don't want to know
your baby's sex, be sure to tell your doctor or ultrasound technician beforehand.)
How safe is ultrasound?
Twenty-year follow-up studies of thousands of mothers and babies who received
diagnostic ultrasound have shown no apparent harmful effects. Depending on the
information desired, ultrasound can be performed at any time during your pregnancy
and repeated ultrasound exams appear to have no harmful effects. Ultrasound
is certainly safer than x-rays.
The other side of the safety question is a theoretical concern about what happens
when these sound waves strike growing fetal tissues. When sound waves bombard
laboratory tissues at high frequencies, they shake up the molecules, heat them,
and produce microscopic gas bubbles in the cell called "cavitation."
Whether this heat or these bubbles damage the cell is unknown, although studies
suggest that the changes demonstrated in research test tubes are insignificant
in babies. Yet this is enough to prompt the National Institutes of Health Task
Force on Diagnostic Ultrasound to conclude: "We could find no evidence
to justify the recommendation that every pregnancy be screened by ultrasound.
In the face of even theoretical risks, where there is no benefit, then the theoretical
risks cannot be justified."
Healthcare providers use the term "diagnostic" ultrasound, implying
there should be a reason for doing the test. It's important that every parent,
like every healthcare provider, approach every test wearing two hats: in the
scientist hat you read or ask about all the benefits and risks of a particular
test and try to weigh them against each other. In the parent hat you consider
your feelings about the test, the information that is sought, and how this will
affect the course of your pregnancy. Scientist, parent, and healthcare provider
all participate in the final decision.
THE BENEFITS OF ULTRASOUND
- Verify whether or not the mother is pregnant. When pregnancy
tests and the usual signs of pregnancy are unclear.
- Detect a possible ectopic pregnancy.
- Obtain a more precise determination of baby's gestational age
when there is a discrepancy between uterine size and estimated due date. In
the first half of pregnancy ultrasound can accurately date baby's gestation
within 7 to 10 days. In later months it is not as accurate and is useless
for dating the pregnancy.
- Evaluate baby's growth if other signs, such as uterine
size, suggest a problem.
- Determine the cause of unexplained bleeding.
- Confirm how baby lies in the uterus (breech, transverse,
vertex) if the clinical signs are unclear late in pregnancy.
- Detect suspected multiple pregnancies if mother's uterus
is growing faster than expected.
- Detect problems with the placenta, such as placenta previa
(the placenta being positioned too low or over the cervix) and abruptio placentae
(the placenta is separating prematurely, causing bleeding).
- Measure the amount of amniotic fluid if mother is losing
amniotic fluid or not replenishing it at a normal rate.
- Detect abnormalities of the uterus, especially in women
with a history of previous miscarriages or problem pregnancies.
- Detect developmental abnormalities in the growing baby
that would influence where baby should be delivered and what preparations
need to be made beforehand. Abnormalities of heart, lung, and intestinal development
can, if detected early, alert parents and healthcare providers to deliver
the baby in facilities equipped to begin management immediately after birth.
Oftentimes, early recognition and early treatment can be lifesaving.
- Assist in medical or surgical procedures: amniocentesis,
chorionic villus sampling, trying to turn a breech baby, fetoscopy, or intrauterine