Korean J Obstet Gynecol.  2009 Feb;52(2):157-165.

Interpretation of antenatal screening methods

• Park IY
• Kwon JY
• Shin JC

Abstract

For definitive antenatal diagnosis of fetal aneuploidy, invasive tests such as chorionic villous sampling, amniocentesis and cordocentesis are required for chromosome analysis. However, to reduce the risk of miscarriage associated with procedural complications, it is important to detect pregnant women with high risk of fetal aneuploidy. Recently, there have been advances in maternal serum and sonographic markers for screening of chromosomal defects in the first and second trimester. The serum screening methods include first trimester screening with nuchal translucency and second trimester multi marker screening. Particularly, combining first and second trimester results can increase the detection rate of Down syndrome with lower false-positive rates. In addition to biochemical markers, second trimester sonogram to detect major and minor sonographic markers for chromosomal defects is important to identify the high risk pregnancy. To detect the fetal aneuploidy with high specificity and sensitivity, we need to interpret the maternal age, the results of first and second trimester serum markers and genetic sonographic findings all together.

Keyword

Fetal aneuploidy; First trimester screening; Second trimester screening; Genetic sonography

MeSH Terms

Abortion, Spontaneous
Amniocentesis
Aneuploidy
Biomarkers
Chorion
Cordocentesis
Down Syndrome
Female
Humans
Mass Screening
Maternal Age
Nuchal Translucency Measurement
Pregnancy
Pregnancy Trimester, First
Pregnancy Trimester, Second
Pregnancy, High-Risk
Pregnant Women
Prenatal Diagnosis
Sensitivity and Specificity