Placenta tissue biopsy,
This is performed from the 12th week of pregnancy onwards to examine the baby’s set of chromosomes. Under constant ultrasound guidance, cells are taken from the placenta through the abdominal wall with a needle. A local anaesthetic is given beforehand.
Provisional findings about the number and structure of the chromosomes is available approx. 24 hours after chorionic villus sampling. The final result, which may differ from the provisional findings in rare cases, can be expected after 2-3 weeks.
Amniocentesis and chorionic villus sampling are invasive procedures and therefore entail a risk.
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