Comparison of Triple and Qadrupple Test in Second Trimester Down Syndrome Screening

Abstract

OBJECTIVE: To compare the Down syndrome detection ratio of triple test and qaudruple test in the second trimester of pregnancy.
STUDY DESIGN: 148 patients whose were admitted to our clinic in the second trimester of their pregnancy were included in this study. All the patients were screened for trisomy 21, trisomy 18 and neural tube defects (NTD) with both triple and quadruple tests. Each patient gave one blood sample and both triple and quadruple tests were studied within the same sample. Any sign of down syndrome, trisomy 18 and NTD was not detected by ultrasound examination. Treshold value for down syndrome is 1/300, for trisomy 18 is 1/300 and for NTD is 1/1000. Amniocentesis was performed to the patients with high test results for trisomy 21 and 18.
RESULTS: There were 6 patients (4.05%) in triple test and 5 patients (3.37%) in quadruple test with high risk results for Down syndrome. In three patient both triple and quadruple tests were reported as high risk. There were 12 patients (8.1%) in high risk group due to maternal age. These patiens were evaluated with amniocentesis and there were no difference between the triple test and quadruple test for detection rates of Down syndrome.
CONCLUSION: In our study we did not find statistical difference between the detection and false positive rates of triple and quadruple tests for trizomi 21 and trizomi 18.