Affiliations: *National Institute of Health, Department of Medical Sciences, Nonthaburi,
Source: Clin Chim Acta 2005; 355: S316
Down syndrome is one of the most important causes of mental retardation in the population. The main aim of this pilot study was to evaluate the sensitivity of maternal serum screening (triple test) to identify women at an increased risk for an affected pregnancy and to reduce the incidence of invasive amniocentesis procedures. Triple test involes combining the maternal age risk with the risks associated with the concentrations of maternal serum alpha-fetoprotein, unconjugated estriol, and human chorionic gonadotropin that are measured by a chemiluminescence immunoassay method. The study consisted of 1000 pregnant women, attending antenatal care unit, Hat Yai Center Hospital. The gestational range for the study group was 14-19 weeks. 171 of these women were considered at increased risk for Down syndrome and 141 of them had an amniocentesis. Among 199 pregnant women over 35 years of age, 93 of them were triple test positive. The results of karyotyping show that there were 4 cases with trisomy 21, 1 case with 47 XXX and 1 case with chromosome translocation. All these chromosome abnormalities were detected in pregnant women over 35 years of age. In conclusions, the use of triple test as a screening tool in our population could reduce the number of amniocenteses, while no cases of Down syndrome would be missed.