Cordocentesis

Cordocentesis

Cordocentesis, also known as percutaneous umbilical blood sampling (PUBS), is a diagnostic prenatal test in which a sample of the baby's blood is removed from the umbilical cord for testing. This procedure is typically performed after the 18th week of pregnancy and is used to detect certain genetic disorders, blood conditions, and infections in the fetus.

Procedure

Cordocentesis is usually performed under ultrasound guidance to ensure the safety of both the mother and the fetus. The procedure involves the following steps:

1. Preparation: The mother is positioned comfortably, and an ultrasound is used to locate the umbilical cord and the fetus. 2. Anesthesia: Local anesthesia may be applied to numb the area where the needle will be inserted. 3. Needle Insertion: A thin, hollow needle is inserted through the mother's abdomen and uterine wall into the umbilical cord. 4. Blood Sampling: A small amount of fetal blood is drawn from the umbilical vein. 5. Post-Procedure Monitoring: After the sample is collected, the fetal heart rate is monitored to ensure there are no complications.

Indications

Cordocentesis is indicated in the following situations:

- Fetal Anemia: To assess and treat fetal anemia, especially in cases of Rh incompatibility. - Genetic Testing: When other tests, such as amniocentesis or chorionic villus sampling, are inconclusive. - Infections: To diagnose fetal infections such as toxoplasmosis or rubella. - Blood Disorders: To evaluate and manage fetal blood disorders like hemophilia or sickle cell disease.

Risks

While cordocentesis is generally safe, it does carry some risks, including:

- Fetal Bleeding: There is a risk of bleeding from the puncture site in the umbilical cord. - Infection: There is a small risk of introducing infection. - Preterm Labor: The procedure may induce preterm labor in some cases. - Fetal Loss: There is a slight risk of miscarriage associated with the procedure.

Alternatives

Alternatives to cordocentesis include:

- Amniocentesis: A procedure where amniotic fluid is sampled to test for genetic conditions. - Chorionic Villus Sampling (CVS): A test that involves taking a sample of placental tissue to test for chromosomal abnormalities.

Also see

• Amniocentesis
• Chorionic Villus Sampling
• Prenatal Testing
• Fetal Medicine