Amniocentesis - is a diagnostic procedure involving transabdominal withdrawal of a small amount of amniotic fluid that surrounds and protects the fetus during its growth and development.
Why is amniocentesis performed?
Amniocentesis is a minimally invasive intervention, mainly used for prenatal diagnosis of chromosomal abnormalities, infections and fetal development disorders, such as spinal cleavage and Down syndrome.
Amniotic fluid contains cells that are produced directly by the fetus. After isolation, these cells subjects itselves to cytogenetic and molecular analysis.
When is amniocentesis performed?
As a rule, amniocentesis is performed starting from the fifteenth week of pregnancy, when the amniotic cavity has reached size that reduces the risk of fetal injury during the study. Preliminary ultrasound is reduced the risk as well
How is the procedure performed?
Under continuous ultrasound monitoring, a specialist inserts a thin needle through the skin into the uterine cavity and reaches the amniotic cavity.
About 15 ml of amniotic fluid is taken. Recall that at the 14th week of pregnancy, amniotic fluid occupies a volume of about 100 ml, which increases by 150-200 ml after 15-30 days and by 500 ml - about the 20th week.
Ultrasonic monitoring of the procedure is harmless to the fetus, allows to control its position, minimizes the risk of possible complications. In the laboratory, a small portion of the amniotic fluid is used to perform direct biochemical tests, and the remaining isolated fetal cells are cultured to obtain a sample for the numerical assessment of the karyotype.
Is the procedure painful?
The amniocentesis procedure itself is not painful, takes several minutes and does not require anesthesia or special hospitalization. After amniocentesis, it is necessary to remain under observation for 30 to 60 minutes. You must refrain from physical exertion for 2 to 3 days. If you suddenly felt abdominal pain or have a fever, you should immediately consult a doctor.
Risks of amniocentesis
Like all invasive procedures, amniocentesis has a certain share of the risk of spontaneous abortion. The chance of a miscarriage is estimated as one in 200. Because of this, it is imortant that the procedure is carried out after the signed consent of an informed pregnant woman who has the right to know in advance about the diagnostic risks.
Amniocentesis cannot be called a mandatory procedure, so parents are solely responsible for their choice.