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Fetal Blood Sampling

Fetal blood sampling is a procedure used to diagnose, treat or monitor various fetal problems. Using a very small needle, specialists in Maternal Fetal Medicine are able to remove a tiny amount of blood from the fetus during pregnancy.

This procedure is performed to:

  • Determine blood type
  • Diagnose genetic or chromosome abnormalities
  • Diagnose possible fetal infections
  • Identify possible fetal anemia (low red blood cell count)
  • Identify possible low platelet count

How is this procedure performed?

  1. This procedure is performed using continuous ultrasound guidance to place a needle through the maternal abdomen into a tiny fetal blood vessel.
  2. A sample of fetal blood can then be sent for testing.

Will I need to have a full bladder?
Sometimes but usually not.

When will I get the results?
Your physician can advise you regarding when to expect the results, as result times do vary depending on the kind of test.


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