Çukurova Universty Faculty of Medicine Gynecology and Obstetrics Clinics chromosome analysis results of first and second trimester anomaly screening tests

Major congenital anomalies are defined in 2-3% of pregnancies during pregnancy or immediately after birth. Prenatal diagnosis consists of invasive diagnostic tests such as amniocentesis, cordocentesis and chorion villus sampling, additional screening and diagnostic tests which are offered to perform patients with higher risk of specific genetic disease, specified sonography and other fetal imaging techniques that identify structural malformation. The aim of our study was to evaluate the chromosomal analysis results that were obtained from amniocentesis (AS), cordocentesis (KS) and chorion villus sampling (CVS) in patients whom had applied to the perinatology unit of Çukurova University Faculty of Medicine (ÇÜTF) gynecology and obstetrics clinic between December 1, 2014 and December 31, 2016 with high risk in terms of chromosome anomaly according to Ultrasonography (USG). Our study was conduct as a retrospective pattern. CVS, amniocentesis and cordosentesis were performed in 1298 pregnant women whom had applied to the Çukurova University Faculty of Medicine, Gynecology and Obstetrics Clinic, Perinatology Unit in the date interval between December 1 2014-December 31 2016 with the indication of abnormal maternal serum screening tests, advanced maternal age, history of abnormal neonatal, history of relatives with Trisomy 21 or abnormalities which were detected by ultrasonography. Data obtained in study were assessed using the SPSS (Statistical Package for Social Sciences) 22.0 package program. The relationship between categorical variables was determined by Chi-Square test. Relationships between normal distribution-matched, numerical data were assessed by ANOVA, Independent Sample t-test, and relationships between non-normal distributions of numerical data were assessed using Mann-Whitney U and Wilcoxon Test. Statistical significance level was determined as p <0.05. 1298 patients were taken to the study. The mean age of the study group was 32.03 ± 6.59 (min-max: 15-50). The mean gestational week of the study group was 16.88 ± 3.63 (min-max: 11-32). Fetal anomalies were observed in 28.9% (n: 366) of the patients while 369 (28.4%) of the 1298 patients who had prenatal diagnosis had abnormalities in the maternal screening results. No chromosomal abnormalities were detected in 1120 (86.2%) of the 1298 patients who were taken into the study. 49 patients had Trisomy 21, 27 patients had Trisomy 18 and 14 patients had Trisomy 13. Turner syndrome was seen in 10 of the patients. In our study, chromosomal abnormality rate of patients with more than one minor marker was found to be statistically significant (p: 0.01). Chromosomal anomaly was detected in 319 (8.4%) of 349 patients with combined test. Chromosomal anomaly was detected in 70 (19.1%) of the 366 patients who detected fetal anomaly. Chromosomal anomaly was detected in 27 (24.1%) of the 112 increased NT patients. Chromosomal anomaly was detected in 29 (% 14.7) of 197 patients with invasive prenatal test with high risk in triple test. Patients who underwent karyotyping due to abnormal combined test results; Trisomy 21 was detected at 2.4%. Trisomy 21 was detected in 5.1% of patients who were karyotyped due to fetal anomaly, Trisomy 18 was detected in 4.6%, Trisomy 13 was detected in 3.2%. Trisomy 21 in 1% of patients who underwent karyotyping due to triple test failure, patients who underwent karyotyping due to NT increase; 13.3% trisomy 21, 5.3% trisomy 18 and 1.7% trisomy 13 were detected. Patients who underwent karyotyping due to advanced maternal age; Trisomy 21 was found in 1.3%, and Trisomy 18 was found in 0.6%. Ventriculomegaly was found in 18.2% of the 137 patients with CNS anomaly detected, and 11.7% of spina bifida was detected. In 6 of 12 patients (50%) who underwent karyotyping due to holoprosencephaly, the diagnosis was trisomy 13. VSD-AVSD was seen in 53.7% of 67 patients who had cardiac anomaly. Chromosomal anomaly was detected in 43.5% of the chromosomal anomalies. Trisomy 18 in 19.4%, trisomy 13 in 11.1% and trisomy 21 in 8.3% were observed of chromosomal anomaly group. The most common minor marker in the studied patients is the increase in the markers of the nuchal fold (17.3%). The rate of chromosomal anomalies in the patients with increased nuchal fold is 4.55%. Our study is a guideline for researchers; in terms of having an experience in tertiary hospital; it has also adds valuable contribution to the literature.