Amniocentesis is an invasive prenatal diagnostic test recommended for women with high risk factors associated to fetal chromosomal abnormalities.
Because of its invasiveness, amniocentesis presents a risk of miscarriage up to 1%.
This invasive prenatal test is usually required in case of:
- Advanced maternal age (over 35 years);
- Family history of chromosomal abnormalities ;
- Previous children affected by chromosomal abnormalities;
- Positivity to prenatal screening tests.
Amniocentesis is performed by inserting a needle into the belly of the pregnant woman, which reaches the amniotic sac and draws a liquid sample (about 15-20 ml).
The belly area subjected to the test is determined through ultrasound monitoring in order to:
- avoid a contact between the needle and the fetus or the placenta
- identify an area with abundance of amniotic fluid.
The amniotic fluid contains the child’s DNA, which is analyzed to detect the presence of chromosomal abnormalities with an accuracy up to 100%.
In some cases it may be necessary to repeat the sampling: this could happen when the amount of collected liquid is insufficient or when cells present in the sample are not sufficient to perform the analysis.
For the 48-72 hours following amniocentesis, pregnant women should remain at rest and avoid efforts.
In some cases, pregnant women may experience pain, fever and small contractions following the drawing. If this happen it's necessary to contact the gynecologist immediately.
Amniocentesis can be performed from the 15th week of pregnancy because from this gestational age there is a sufficient amount of amniotic fluid for picking and analyzing cells' DNA.
Usually, results are available within 20 days but in case of specific analysis (i.e. detection of rare genetic diseases) reporting could require more days.
An analysis of amniotic fluid can detect Down Syndrome, sex chromosome abnormalities and developmental issues (i.e. Spina bifida)
If you are not at risk consult your gynecologist to avoid the risks of amniocentesis with the prenatal test of next-generation AURORA.
