may be times during pregnancy when you or your prenatal
care provider would like to know more about your baby’s
health and development. One of the tests your doctor or
midwife may recommend is amniocentesis. This article contains
answers to common questions about amniocentesis.
Amniocentesis is a prenatal test in which a small sample
of amniotic fluid is taken out and tested. Amniotic fluid
is the “water” that is around the baby inside
is Amniocentesis Done?
There are many tests that can be done using amniotic fluid:
How is Amniocentesis Done?
Amniocentesis can be done at a clinic or hospital. First,
the doctor uses ultrasound to find a pocket of fluid that
is safely away from the baby and the placenta. The woman’s
belly is then cleaned with iodine. Next, the doctor puts
a long thin needle through the woman’s belly, into
the amniotic sac. About one to two tablespoons of fluid
is taken out, and the needle is pulled out. If the woman
has twins, a sample is taken from each sac. Last, the baby’s
heartbeat is checked. The test usually takes only a few
minutes. Most women feel pressure and mild discomfort during
Should I Expect after the Amniocentesis?
After amniocentesis you should plan to take it easy and
avoid heavy lifting, exercise and sex for one or two days.
You may feel slight cramping for about a day. If your blood
is Rh negative, you will get a shot of RhoGAM. Check with
your doctor if you have fluid leaking from your belly, major
cramping, spotting, or fever.
Problems after amniocentesis are rare, but may occur. It
is up to you to decide whether or not you want to have an
amniocentesis done. It is a good idea to talk about the
risks and benefits of the test with your doctor, your partner,
and/or a genetic counselor.
According to the Centers for Disease Control (CDC), the
rate of miscarriage due to amniocentesis is 1 in 200 to
400 (or 1/4 to 1/2 of one percent). The risk of miscarriage
goes down if it is done later in pregnancy. There is also
a very low risk of infection in the uterus after the test
(about one in 1,000). Rarely, the needle may touch the baby
during the test, but it is usually harmless. Doctors use
an ultrasound during the test to avoid touching the baby.
Soon Will I Know the Results of the Test?
It depends on the type of test. Some tests for lung maturity
are done in a few minutes. Genetic tests usually take about
seven to ten days because the cells must be grown in a lab
before they are tested.
is the Difference Between Chorionic Villus Sampling (CVS)
CVS is a test in which a few cells are taken from the place
where the placenta meets the uterus. It is done between
the 10th and 12th week of pregnancy. CVS helps doctors find
genetic problems earlier than amniocentesis, but the test
has a higher risk of miscarriage. It is a newer test than
amniocentesis, so it isn’t offered in all areas. Also,
CVS does not test for neural tube defects such as spina
you have more questions about amniocentesis, contact your
prenatal care provider. This article is for informational
purposes only, and does not replace the advice of a doctor
or certified nurse midwife.
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