Journal List > Korean J Obstet Gynecol > v.53(12) > 1006367

Jung: Prenatal screening for Down syndrome

Abstract

In the past decades, numerous markers and strategies for Down syndrome screening have been developed. With the recent acceptance of first trimester and integrated screening as a part of routine clinical practice, there are now a variety of accepted screening protocols for Down syndrome. These choices can be confusing both to patients and clinicians. First trimester screening is at least as accurate as traditional second trimester screening and provides results earlier. Combining first and second trimester results increases the sensitivity and specificity of screening and reduces the number of women requiring invasive testing. However, the decision to screen and to perform invasive confirmative testing is a personal one that may be influenced by the presence or absence of a family history of aneuploidy or genetic disorders and by the woman's obstetrical and medical history, attitudes and beliefs about termination of pregnancy, education, religious beliefs, and economic concerns. The purpose of this article is to outline the various options in prenatal screening, and their individual advantages and disadvantages.

Figures and Tables

Table 1
Down syndrome screening tests and false positive rate8
kjog-53-1041-i001

FPR: false positive rate, DR: detection rate, NT: nuchal translucency, PAPP-A: pregnancy associated plasma protein A, AFP: alpha-fetoprotein, hCG: human chorionic gonadotropin, uE3: unconjugated estriol.

*NT and/or serum measurements at 12 completed weeks of pregnancy.

Table 2
Combined first-trimester screening prospective study outcomes (5% false positive rate)
kjog-53-1041-i002

BUN: first trimester maternal serum biochemistry and ultrasound fetal nuchal translucency screening, FASTER: First and Second Trimester Evaluation of Risk, SURUSS: the results of the Serum, Urine and Ultrasound Screening Study, OSCAR: one-stop clinic for assessment of risk for fetal anomalies.

Table 3
Down Syndrome screening tests and detection rates (5% false positive rate)
kjog-53-1041-i003

NT: nuchal translucency, PAPP-A: pregnancy associated plasma protein A, hCG: human chorionic gonadotropin, MSAFP: maternal serum alpha-fetoprotein.

*Reference 10, Reference 18.

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