Chorion biopsy is a study that allows you to detect congenital and hereditary pathologies in early pregnancy. With it, samples of the chorion are taken, which later forms the placenta.
It is worth noting that no manipulations with the fetus itself are carried out, so the chorion biopsy is considered quite safe. After the procedure, the risk of spontaneous abortion is only 2%. This study gives accurate results, but is painful and can cause severe discomfort to the pregnant woman, therefore, it is carried out strictly according to indications. It takes very little time, and the results are ready in 3-4 days.
There are 2 main types of this manipulation:
• Vaginal chorionic villus sampling - performed between 8 and 12 weeks of gestation. Under ultrasound control, a special instrument is inserted into the uterus through the vagina, which is placed between the endometrium and the chorion (it is the fetal membrane). With this manipulation, the villi on the chorion are cut off or absorbed. In the future, they are subject to laboratory research. This procedure is absolutelypainless.
• Abdominal chorionic villus biopsy - done between 9 and 11 weeks of pregnancy. Sometimes this manipulation can be used in the second and third trimester, as it allows you to quickly get results, especially in cases where there is little amniotic fluid, so amniopuncture is not possible. For manipulation, the patient lies on her back. The doctor, using an ultrasound machine, determines the position of the placenta, uterine walls, and also finds out the future safe puncture site. To take the necessary material with one needle, a puncture of the abdominal and uterine walls is performed, with the other, a cell sample is taken for further research. It is worth noting that the puncture site must be treated with a local anesthetic with good analgesic properties.
Chorion biopsy is most often prescribed for pregnant women who are at increased risk of having a baby with genetic disorders, although any woman can have this test during pregnancy if desired.
What pathologies can be detected using this diagnostic technique? This is primarily Down's syndrome, trisomy 13 and 18 chromosomes, Turner's syndrome, cystic fibrosis and sickle cell anemia, as well as Klinefelter's syndrome. In addition, a chorionic biopsy can detect about 100 more chromosomal and genetic abnormalities.
It is worth noting the important advantage of this diagnosis - it can be used much earlier than amniocentesis (already at 10 weeks of gestation). Exceptthis, the results can be obtained quite quickly - in most cases in the first week after the examination.
I must say that a chorionic biopsy can also reveal placental mosaicism, when some cells have a normal chromosome set, while others have formed with certain anomalies.
After the examination, spotting and cramping pains in the abdomen may appear. Amniotic fluid can also be released from the vagina (in a small amount). If you experience any unusual symptoms, you should contact the doctor who is managing the pregnancy.
