Chorionic villus sampling and amniocentesis

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Choriocentesis and amniocentesis

Supporting diagnostics

What is choriocentesis?

Choriocentesis is performed from week 11 of pregnancy onwards and involves taking a sample fragment of the placenta. The sample is obtained via the transcervical or transabdominal route, guided by ultrasound.

What is amniocentesis?

Amniocentesis is performed from week 15 of pregnancy onwards. The doctor samples a few millilitres of the amniotic fluid surrounding the foetus. This sample is obtained through the mother’s abdominal wall using a needle and is guided by ultrasound.

The two investigations are performed on an outpatient basis and no anaesthetic is required. The risk of miscarriage your child is 0.5 to 1%.

FISH: trisomy 21 (three red spots)

QF-PCR: trisomy 21 (three peaks)

Chromosome analysis

Performed with the help of choriocentesis or amniocentesis and designed for rapid analysis, some recent methods (FISH or QF-PCR) can deliver preliminary results within 24 to 48 hours. Definitive results, based on the culture of foetal cells, are available after two to three weeks.