Prenatal Diagnosis of Genetic Diseases
A definite diagnosis can be made whether the baby in the womb has genetic diseases or not. At this point, the important thing is that for which pregnancies the exact diagnosis method will be used.
It is important to screen all pregnant women with detailed ultrasonography and to determine their risks by using special screening methods for special risk groups.
Some examples of pregnancies with increased risk in this respect are given below.
Expectant mothers older than 35
Mothers with recurrent miscarriages
Couples with abnormal pregnancies
Couples with genetic diseases
Couples with an inherited disease in their families
How to Diagnose Genetic Diseases During Pregnancy?
Examination of Prospective Mother and Father: If the mother or father has genetic diseases, the chromosome map of the mother and father is mapped when necessary. In this way, the risk of genetic diseases in the child is analyzed.
Ultrasonography: Since structural and functional anomalies can be detected by ultrasonography and can enable the investigation of genetic diseases that may be related, detailed fetal ultrasonography is almost the most important examination to be done during pregnancy.
It is generally applied in two ways. The first one is early detailed ultrasonography and genetic screening test consultancy between 11-14 weeks, and the second one is detailed fetal ultrasonography performed between 20-23 weeks.
Triple test: Triple test; By measuring hormone levels and analyzing these hormone values, Down syndrome and trisomy risks are determined. Although this test does not diagnose, it is quite successful at analyzing the risk.
Chorionic villus sampling (CVS): In CVS application, a very small sample is taken from the baby’s placenta. Then the tissues of the fetus are analyzed by means of genetic examinations. Its chromosome map is created. As from the 11th week of pregnancy, genetic diseases can be diagnosed.
Amniocentesis: A small amount (usually 15-20 cc) of sample is taken from the amniotic fluid where the baby is in. In general, this process is done between 16-20 weeks.
Cordocentesis: Cordocentesis is performed by taking a small amount of blood (usually 1-2 cc) from the baby’s umbilical cord in the later stages of pregnancy. With this test performed after the 20th week of pregnancy, various diseases are diagnosed.
Cell-Free Fetal DNA Test in Maternal Blood: It is another test that has been developed and used in recent years, where the genetic structure of the baby can be examined by taking blood from the mother. This test is known as “cell-free fetal DNA in maternal blood or cffDNA or non-invasive prenatal test, NIPT test” and screening for Down syndrome with 99% success rate can be done. It is the most successful of the screening tests.