Prenatal/CVS Testing

A carrier should find out the carrier status of his or her spouse. If both, you and your partner/to-be-partner, are carriers of the Thalassaemia gene, there is a 25% chance of your child being affected by Thalassaemia Major. Hence, it is necessary for the mother to have her CVS (Chorionic Villus Sampling) Test done during pregnancy. The ideal time for CVS test is during the 12th- 13th week of pregnancy. Sampling is only performed by a trained gynecologist. It involves taking a small tissue from the placenta.


Chance of Miscarriage During or after CVS

As CVS is an invasive test, it is done at 12th - 13th week of pregnancy. The risk of having a miscarriage after CVS is about 1%. Informed consent is taken from the couple after the genetic counseling, before performing the test. Complete rest for 24 hours is recommended after the test to minimize the risk of miscarriage.


What you need to bring along

  • An ultrasound report of the mother around the 11th week of pregnancy
  • Screening test report of Hepatitis B and C of the mother
  • Blood Group & Rh factor report of the mother 


Is CVS painful?

Most women say that having CVS is not a painful procedure. Some feel mild pain. Women also say they feel anxious before the test. Woman may notice some cramping for a few hours afterwards. She will feel normal after 1-2 hours.


Key Points

  • Thalassaemia Minor or Thalassaemia Carrier or Thalassemia trait is the same thing.
  • Thalassaemia Minor/Carrier/Trait does NOT mean that you have Thalassaemia Disease. You live a normal life.
  • Thalassaemia Minor/Carriers/Trait may transfer the one defected gene to their children.
  • Being a Thalassaemia Minor/Carrier/Trait does NOT mean that you should not get married.
  • A Thalassaemia affected child will only be born if BOTH parents are Carriers. There is 25% (1 in 4) chance of two carriers giving birth to a Thalassaemia Major Child.
  • If only ONE parent is determined to be Carrier and the other is Normal, then there is no chance of birth of Thalassaemia affected child.
  • Premarital screening may be helpful to determine if your future partner and you are a Carrier or not.
  • If both parents are carriers, then prenatal diagnosis ( CVS,Chorionic Villous Sampling)  is offered during the 12th to 13th week of pregnancy to determine the status of the unborn child whether he/she is Thalassaemia Major or Minor/Carrier/Normal.


CVS Test Results

There can be three types of tests results:

  • Normal
  • Affected (Thalassaemia Major)
  • Thalassaemia Minor/Carrier

If your CVS test result comes out to be Normal or Carrier/Minor, then the pregnancy is continued and the child is safe.

However, if the result comes out to be Thalassaemia Major and the child is affected, the couple needs counseling to decide about future of this pregnancy.