Amniocentesis: when to do it, the risks and the cost
Amniocentesis is an examination that consists of a transabdominal sampling of amniotic fluid from the uterus. With this procedure, biological samples are obtained that allow for the so-called prenatal diagnosis. In fact, this test allows to identify chromosomal problems, in particular trisomies 21 (the so-called Down syndrome), 18 and 13, hereditary diseases of the fetus and some diseases of the central nervous system.
The fetal cells present in the liquid sample are cultured in vitro for 15-20 days and subjected to examination of the chromosomes to identify any anomalies or to search for specific genetic mutations. It is possible to have a quick result, within 24-48 hours of collection, related to the most frequent chromosomal anomalies: trisomies 21, 18, 13 and alterations of chromosomes X and Y, waiting for the complete result.
Thanks to the analysis of the amniotic fluid taken, the karyotype of the fetus is then established, that is, its chromosomal "identity card".
If the analysis of the amniotic fluid reveals an abnormality of the fetal karyotype, the parents can decide, with the help of doctors, to resort to abortion. If your doctor has recommended an amniocentesis, you can learn more about the reasons that lead to this examination, its procedure and the risks associated with it, always bearing in mind that amniocentesis is not mandatory.
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When is it recommended to do an amniocentesis?
Amniocentesis is usually recommended or even recommended for women over the age of 35 because with age the cases of chromosomal abnormalities increase (in particular trisomy 21). It is also recommended in cases where there is a high risk of hereditary diseases or families with previous cases of Down Syndrome, or when the bitest is positive. Amniocentesis is also indicated when a fetal abnormality has been detected ultrasonographically and in the case of contraction of infectious diseases such as cytomegalovirus, toxoplasmosis or rubella.
Sometimes some women refuse to undergo this examination, for ethical or personal reasons, but in any case if the doctor prescribes amniocentesis or strongly recommends it, it means that there is a motivation dictated by medical reasons. In any case, even before the amniocentesis it is possible to undergo another prenatal diagnostic test, the villocentesis.
Here is the video that explains when to do the amniocentesis and the CVS
From what week of pregnancy can it be done?
Amniocentesis can be performed from the sixteenth week of pregnancy. It is systematically proposed when pregnancy presents clear-cut risks and to all future mothers aged 35 and over. It can also be prescribed later, beyond the twentieth week in the case of pregnancies at risk, such as those in which the incompatibility of the Rh factor occurs, if there is a suspected neurological or digestive malformation and, again, in cases of fetal intolerance requiring immediate intervention.
Yes or no? The obligation to inform to decide whether to do it
Every woman who is in a situation of uncertainty must have the opportunity to clarify any doubts and then ask the doctor all the questions she wishes. In turn, the doctor has a legal obligation to respond and offer all information on the amniocentesis and all the consequences and risks associated with it. Every future mother must be fully aware of why to carry out this examination. This is in fact the only way to face the amniocentesis with confidence and serenity. In any case, before the examination is carried out, the expectant mother signs the so-called informed consent for the execution of the amniocentesis, certifying that she is aware of all the information.
How is an "amniocentesis performed?"
First of all, a morphology is performed which determines any abnormalities in the fetus. Cardiac activity, the extension of the placenta, the walls of the uterus are observed. The doctor then focuses on the position of the fetus and the amniotic fluid. The point of insertion of the needle is chosen, away from the placenta and the fetal head. Crossing the abdominal wall, 15-20 ml of amniotic fluid is taken. Despite the absence of anesthesia, the mother does not feel pain, but only a simple discomfort, like what is perceived with a normal puncture. The gauge of the needle is in fact very thin.
How long does it last?
The duration of the amniocentesis is thirty minutes maximum, including ultrasound. Small difficulties may arise, for example if the placenta is positioned in the front of the uterus or if the mother has a negative Rh factor. In this case it is necessary to administer anti-D immunoglobulins to prevent any Rh immunization. In any case, after the withdrawal, expectant mothers are recommended to rest for two days, not to make any effort and possibly to remain quiet at home. In case of contractions, cramps, loss of blood or fluid, it is advisable to contact a doctor immediately.
The risks for mother and baby
Amniocentesis carries a risk of abortion of 0.5-1%, that is, one for every 200 samples taken. The gesture is also a little uncomfortable: the idea of a needle being inserted in the belly, close to the fetus, can make a certain impression. In reality, the fetus is not at risk and the sensation that mothers experience is that of a simple sting. In any case, it is always advisable to contact a specialist with proven experience, both to obtain information and to carry out the examination.
How much does it cost to do an "amniocentesis?
How much does an amniocentesis cost? If you go to a public hospital, the amniocentesis ranges from 600-700 euros to test the main chromosomal diseases and trisomies (such as Down's Syndrome) to 800-1000 euros for more in-depth examinations in search for any rarer diseases. The National Health Service, on the other hand, provides free amniocentesis for women over 35, or for cases in which there are proven risk factors for chromosomal diseases, such as heredity or the presence of other children with chromosomal diseases.
For more useful information on amniocentesis, you can visit the website of the Veronesi Foundation.