Print Friendly

Amniocentesis is a prenatal test used to look for certain birth defects and genetic problems in the developing baby. It is usually recommended following  an abnormal triple test result.


Using an ultrasound as a guide, a safe area is located for a needle to enter the amniotic sac and safely remove a small amount of fluid that surrounds the baby. The amniotic fluid is taken to the lab for analysis. Results usually come back in a couple of weeks. In the lab , the amniotic fluid which contains cells shed by the fetus is analyzed to check for alpha fetoprotein levels. A host of other tests and genetic studies are also done.


This procedure may be done for many reasons including

  • done to check for genetic and chromosomal problems in a fetus such as down syndrome, anencephaly and rare metabolic syndromes that are inherited
  • if you have a child or previous pregnancy with birth defect
  • if you are 35 years of age and above
  • if you have a family history of genetic disorders such as sickle-cell anemia or Rh incompatibility.
  • diagnose an infection in the developing baby
  • to check for spinal bifida and other neural tube defects


Complications from amniocentesis are rare but may include the following

  • miscarriage
  • vaginal bleeding
  • infection or injury to baby
  • leaking amniotic fluid

This procedure is usually done between 14 and 20 weeks although some facilities may do it as early as 11 weeks. It may also be done late in the third trimester to check for infections in the baby or to check if baby’s lungs are matured enough for early birth.

Amniocentesis. March of Dimes. Accessed January 3, 2014

Amniocentesis. National Library of Medicine. MedlinePlus. Accessed January 3, 2014

Amniocentesis. American Pregnancy Association. Accessed January 3, 2014

The American Heritage® Stedman’s Medical Dictionary. Retrieved January 2014 from website.

Leave a Reply