Esra ÇOLAK GENIŞ, Fethi Sırrı ÇAM
Meandros Medical and Dental Journal - 2026;27(1):100-107
Objective: Prenatal diagnosis refers to the detection of fetal and embryonic chromosomal abnormalities during the antenatal period using appropriate methods based on gestational age. This study aimed to identify chromosomal abnormalities in high-risk pregnancies, determine their frequency, and highlight their clinical significance. Materials and Methods: This retrospective study included 1152 pregnant women who were recruited between January 2013 and December 2023. During this period, 774 amniocentesis cases, 155 chorionic villus sampling (CVS), 153 abortions, and 70 fetal blood samples (cord blood) were analyzed. All samples were stained with Giemsa trypsin banding using cell culture protocols specific to the material, and 20 metaphase chromosomes were analyzed using G-banded imaging systems. The 2016 International System for Human Cytogenetic Nomenclature (ISCN) was used for cytogenetic evaluation. Results: Abnormal karyotypes were found in 49 of 774 (6.33%) amniotic fluid samples, 16 of 155 (10.32%) chorionic villus (CVS) samples, 13 of 153 (8.49%) prenatal evacuation materials, and 8 of 70 (11.42%) fetal blood studies. The most frequently detected chromosomal abnormality across all sample types was trisomy 21, followed by trisomy 18, trisomy 13, and sex chromosomal abnormalities. Conclusion: Despite the emergence of new technologies in prenatal diagnosis, fetal karyotyping remains a necessary and valuable method. It remains effective for diagnosing fetal anomalies and providing genetic counseling. Identifying chromosomal abnormalities in high-risk pregnancies is informative for subsequent pregnancies. Family studies are conducted in patients with structural chromosomal abnormalities. Prenatal and preimplantation genetic diagnoses are recommended for patients with familial carriers.
