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The article presents the author's views on the non-invasive prenatal testing (NIPT) for pregnant women who want to detect trisomy 21 in their unborn child. It states that NIPT improve the quality of prenatal testing for fetal abnormalities. It further discusses aneuploidy screening, chromosomal microarray analysis and testing in pregnancy.

ABSTRACT A 35-year-old primigravida, pregnant after in-vitro fertilization, was seen because of a trisomy 13/trisomy 18 ( T13/ T18) risk of 1:55, based on the result of her first-trimester combined test. She elected for non-invasive prenatal testing ( NIPT) at 14 + 5 weeks' gestation, which was positive for T13. After counseling, the patient elected to undergo amniocentesis. Quantitative fluorescence polymerase chain reaction ( QF-PCR) showed no signs of trisomy, and full karyotyping confirmed a normal 46,XY result. Analysis of the published literature on NIPT for T13 gives an overall detection rate of 91.6%, with a false-positive rate of 0.097%. Based on this detection rate, hypothetical calculations show that the positive predictive value is highly dependent on the prevalence of the disease, resulting in an unfavorable balance between benefit and harm in a general population. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Background: Both pregnant women and providers of obstetric care are aware of the rapid advances in noninvasive prenatal diagnosis (NIPD) of fetal trisomies, and appear to look forward to its clinical introduction. Objectives: To review and critically assess the published literature on diagnostic accuracy of NIPD using cell-free fetal DNA or RNA in maternal blood to detect fetal trisomy 21. Method: An electronic search was performed in MEDLINE, EMBASE and the Cochrane library (1997 to April 2011). Of a total of 201 citations, 9 studies were eligible for full-text analysis by 2 independent reviewers, using the QUADAS tool. Results: Two of the 9 analyzed studies complied with the criteria of the QUADAS tool. Combining the selected 2 studies, with a total of 681 pregnancies included, overall sensitivity was 125/125 (100%, 95% CI 97.5-100%) and specificity 552/556 (99.3%, 95% CI 98.7-99.3%). Conclusions: NIPD of fetal trisomy 21, using fetal nucleic acids in maternal plasma, appears to have a high diagnostic accuracy. Large-scale prospective studies are awaited before implementation in clinical practice. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]