Maternal Serum Screening for Downs Syndrome, Open Neural Tube Defects and Trisomy 18

Abstract Maternal serum screening identifies women at an increased risk of a pregnancy with Down's syndrome or trisomy 18 or an open neural tube defect. The triple test, consisting of maternal serum α-fetoprotein, unconjugated estriol and human chorionic gonadotropin was carried out by a chemiluminescence immunoassay method in our laboratory. The study consisted of 373 pregnant women. The gestational range for the study group was 14–22 weeks. The mean maternal age for the study group was 28.53 ± 5.46 years (range 17.4 to 43.5 years); 9.1% of the women were considered at high risk for Down's syndrome based on the test results. In our study the detection rate for Down's syndrome by prenatal karyotyping was 66.6%. Maternal serum screening allows reduction of the number of women requiring amniocentesis without a significant decrease in the detection rate.