AMNIOCENTESIS

Amniocentesis is an important test in prenatal diagnosis: under constant guidance with the help of the ultrasound, a 20-22 Gauge needle is inserted in the abdominal wall passing through to the amniotic sac where a sample of amniotic fluid is withdrawn, which is then sent for laboratory analysis.

The procedure can be performed after the completed 15th week of pregnancy, in an outpatient facility without the need of anaesthesia.
Reporting times are 3 days for a preliminary result (QF-PCR); for the conclusive results (culturing method) it takes about 20 days.

The objectives of amniocentesis, according to the indications, can be summarised as follows:

FOETAL KARYOTYPE:

• Mother’s age = 35 years or older
• Previous foetal aneuploidy
• chromosomal rearrangements in the parents
• family history of aneuploidy                                                                         
• second trimester screening has suggested there may be a problem
• foetal malformations detected during ultrasound examination
• mosaicism diagnosed by chorionic villus samples (CVS)
• sex diagnosis for illnesses related to chromosome X.

DNA ANALYSIS:

• suspected infectious disease from mother to child (Cytomegalovirus, Toxoplasmosis, Rubella, Parvovirus B19) by means of PCR quantitative.
• determining foetal Rh (also on the mother’s blood after the 9th week).
• genetic diseases.
• Inborn errors of metabolism.

BIOCHEMICAL TESTS:

• inborn errors of metabolism.
• neural tube defects.