Cord blood sampling is a test that is carried out to assess the
possibility of your baby having any genetic defect. The test, also
called as percutaneous umbilical cord blood sampling (PUBS) or
cordocentesis, will be conducted by a qualified physician who will draw
blood from your baby's umbilical cord and then send it to a laboratory
for the requisite genetic tests.
This test is performed when there are inconclusive results being obtained from other tests like amniocentesis (where the amniotic fluid surrounding the baby is sampled) or chorionic villus sampling (CVS) and ultrasound.
Cordocentesis is usually performed after 17 weeks' gestation. One of the main advantages of this test is that it allows the doctor to asses if your baby has severe anemia or low blood volume. In such a condition, your physician will advise for a blood transfusion.
All women need not submit to cord blood sampling. Only those women whose pregnancies are deemed to be at high risk are advised to undergo this procedure, which is not without risks by itself.
If you have a family history of any genetic conditions like thalassemia, you may be better off by getting this test done to rule out the presence of similar defects in your baby. Women who have late pregnancies are also at risk of conceiving babies with certain genetic defects. Doctors will also advise such women to undergo cordocentesis.
An advanced imaging ultrasound will determine the exact location where the umbilical cord inserts into the placenta. Your doctor will use this as a guide to insert a thin needle through your abdomen and uterus and into the umbilical cord. Here a small sample of fetal cord blood is drawn.
Your doctor will then send this sample to the laboratory for chromosomal analysis. The test results are usually obtained within 72 hours.
What does cord blood sampling tell me?
According to the American pregnancy Association, cordocentesis will look for the presence of the following abnormalities:
* Malformations of the fetus
* Fetal infections like rubella and toxoplasmosis
* Fetal platelet count in the mother
* Fetal anemia
Are there any risks for my baby or me from this procedure?
Yes, there is a high risk of miscarriage during the procedure. Additionally there could also be blood loss at the puncture site, decrease in the fetal heart rate infection, and premature rupture of membranes. You may feel some pain like a menstrual cramp during the procedure, which lasts for about 45 minutes.
You are advised to contact your physician if you have fever, chills or leakage of amniotic fluid after the test.
What happens if the test indicates presence of some abnormalities in my baby?
Your doctor will reveal test results and will also advise on the best course to proceed with a special needs baby. You and your family can begin planning on lifestyle modifications needed to look after the baby.
Additionally the results, if abnormal, will also allow you to make a decision about carrying the child to term