Chorionic villus sampling: costs and results

The chorionic villi biopsy is a very reliable prenatal test to detect malformations, hereditary diseases and chromosomal abnormalities, such as Down syndrome, in your unborn child. It is sometimes preferred to amniocentesis because it can be done earlier in the pregnancy. Many expectant mothers associate this with the hope of an early result. It is an optional investigation. So you can decide for yourself whether you want to have it done.

Reasons for a chorionic villus biopsy

• The parents-to-be want a chromosome analysis.
• The nuchal translucency measurement yielded conspicuous findings.
• After the ultrasound examination, there is a suspicion of a malformation.
• There are already genetic diseases in the family that could be passed on to the child.
• Siblings are already suffering from a hereditary disease.
• There is an infection.
• The Rhesus factor (protein on the cell membrane of the red blood cells) is to be determined.

In particular, women over the age of 35 are more likely to choose to have a chorionic villus biopsy performed. With increasing age, the risk of malformations and chromosomal disorders in your baby increases. If your doctor determines that it is medically necessary, the test will usually be covered by your health insurance company. Otherwise, the chorionic villus biopsy can cost you around 43 to 100 euros.

Chorionic villi – your child’s genetic material

The chorion forms the layer of cells on the outside of the amniotic sac and is usually made of the same genetic material as your child. The tissue of the chorion has small finger-shaped protuberances on the surface, the so-called chorionic villi. As the pregnancy progresses, the villi settle and form the exchange of substances between you and your child. The chorionic tissue from these villi can be used to study your child’s genetic makeup and chromosomes.

What happens during a chorionic villus biopsy?

A chorionic villus biopsy examines your baby’s chromosomes. Tissue is removed from your placenta, the chorionic villi mentioned above. The whole test takes about half an hour. Taking the sample, on the other hand, only takes a few minutes.

Your doctor will start with an ultrasound scan to see what week of pregnancy you are in and to locate the placenta. Depending on the position of the placenta, your doctor can choose two different types of cell collection. The first possibility is: Your gynecologist carries out a so-called “puncture”. He inserts a hollow needle through the abdominal wall into the placenta . Tissue is removed from the placenta. At the same time, the course of the examination is constantly checked by ultrasound. The puncture site is anesthetized beforehand. This form of chorionic villus sampling differs little from amniocentesis. Amniotic fluid is taken from her to examine the chromosomes, and tissue for the chorionic villus biopsy. Alternatively, your doctor can also perform the tissue removal vaginally. He inserts a fine tube into your vagina and cervix and removes the necessary tissue.

Results of chorionic villus sampling

A so-called karyogram is created in the laboratory from the genetic material obtained in order to visualize the chromosome set. With the help of this karyogram, changes in the number of chromosomes, such as those that occur in trisomies, but also breaks and faulty fusions in the chromosomes can be determined. The gender of the child can also be identified. The first results of a chorionic villus biopsy are usually available after one to eight days. They are already quite comprehensive. So you have relative certainty early on. More detailed test results will follow after about two weeks, because your child’s tissue samples must be created as a long-term culture. In rare cases, the culture of the cells can fail at this point. Then, unfortunately, another withdrawal is necessary.

After the examination

Tests like a chorionic villus biopsy can be stressful for you as a pregnant woman, both physically and mentally. Which mother-to-be would like to think about possible deformities in her baby. Rest after the exam and try to relax. Try to avoid any physical exertion for the next three days. There may be slight vaginal bleeding for the next 24 hours after the chorionic villus sampling. This is a completely normal side effect. Regardless, you should let your doctor know. If you lose a clear liquid during the bleeding, you should contact your doctor immediately.

To be performed only by qualified physicians

The chorionic villus biopsy is only performed in suitable facilities that have been awarded level 3 by the German Society for Ultrasound in Medicine (DEGUM). Since the chorionic villus biopsy requires a steady hand from the doctor performing the tissue removal, this is entirely justified.

Disadvantages of chorionic villus sampling

• The risk of miscarriage with a chorionic villus biopsy is about 0.5 to 1 percent. It is therefore considered to be higher than in the amniocentesis test.
• If you have the test performed before the 10th week of pregnancy , the child may be injured. In severe cases, limb deformities can occur. However, this is rare.
• With chorionic villus sampling, more often than with other examinations, the material obtained cannot be used in long-term cultures. Then the procedure has to be repeated.
• Unfortunately, unlike the amniotic fluid test, the disease spina bifida (spinal cord damage) cannot be detected with a chorionic villus biopsy.