Amniocentisis

 Amniocentesis is an antenatal allows clinicians to check whether a foetus potentially has a genetic or chromosomal condition such as Patau's Syndrome or Downs Syndrome, both caused by trisomy (Patau syndrome= trisomy 13 and Downs Syndrome= trisomy 21). It is done by a needle being inserted into the amniotic sack and withdrawing a sample of amniotic fluid cells.

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