Effectiveness of Quadruple test for Down syndrome screening pregnant women at Regional Health Promotion Center 7, Khon Kaen

Abstract

Down syndrome is a genetic disorder caused by an extra copy of chromosome 21, leading to multisystem abnormalities. Traditionally, amniocentesis has been used to detect these abnormalities, but it carries risks of miscarriage or complications. Therefore, the Ministry of Public Health has implemented preventive measures to reduce the incidence of Down syndrome in pregnant women by using the Quadruple test. This study aims to evaluate the incidence and effectiveness of the Quadruple test for screening Down syndrome in comparison to chromosomal testing from amniotic fluid in 18,695 pregnant women. Among these, 1,908 women (10.21%) received positive results. Of the positive cases, 1,570 (82.29%) underwent amniocentesis for chromosomal testing, with 36 cases (2.29%) diagnosed with Down syndrome (Trisomy 21), 1 case (0.06%) with Trisomy 18, and 35 cases (2.23%) with other abnormalities. There were 338 cases (17.71%) where amniocentesis was not performed. The Quadruple test demonstrated a sensitivity of 94.7% (95% CI: 94.41 - 95.06) and a specificity of 91.6% (95% CI: 91.23-92.03). The diagnostic value for those who received negative screening results was high, with a negative likelihood ratio of 0.06 (95%CI: 0.01-0.22), while the positive likelihood ratio for those with positive screening results was high at 11.27 (95%CI: 10.83-11.84). These results indicate that the Quadruple test remains an effective and suitable screening method for detecting Down syndrome in pregnant women across all age groups.