Amniocentesis

What it means?
It means taking out amniotic fluid from the pockets of fluid surrounding the baby and submitting this fluid to a genetic laboratory for various tests.

Who are suitable candidates?
Various indications for amniocentesis are:-

  • Abnormal triple test
  • Suspicion of genetic abnormalities on ultrasound
  • Known genetic disease in family e.g. Thalassaemia, DMD, etc.
  • Older women
  • Previously affected baby

Who should not get amniocentesis?

  • History of recurrent abortions
  • Normal NIPT
  • Confirmed abnormality on ultrasound
  • Vaginal bleeding

What are its main steps?

  • Counselling and consent
  • Aspiration of amniotic fluid under local anaesthesia and ultrasound guidance
  • Dispatch the sample to genetic laboratory FISH test or karyotype
  • Receipt of report
  • Reassurance and counselling if normal
  • MTP if abnormal

Advantages:

  • Highly reliable and confirmatory test
  • Simple and safe day care procedure
  • No after care required

Disadvantages:

  • Abortion risk > 5 to 1%
  • Cost
  • Rarely failure of lab to give a report
  • Delay of 2-3 weeks in getting the report
  • Not all diseases can be diagnosed
  • Limited genetic labs

Legal issues:

  • Amniocentesis can only be done in authorized centres and authorized laboratories only can test the samples.
  • MTP can only be done before 20 weeks.
  • Appropriate forms and records need to be filled and saved.