Clinical experience from Thailand: noninvasive prenatal testing as screening tests for trisomies 21, 18 and 13 in 4736 pregnancies

Prenat Diagn. 2016 Mar;36(3):224-31. doi: 10.1002/pd.4775. Epub 2016 Feb 15.


Purpose: The purpose of this article is to report the clinical experience and performance of massively parallel sequencing-based noninvasive prenatal testing (NIPT) as a screening method in detecting trisomy 21, 18, and 13 (T21/T18/T13) in a mixed-risk population in Thailand.

Methods: In a 30-month period, 121 medical centers in Thailand offered NIPT as clinical screening tests for fetal T21, T18, and T13 in the mixed-risk population. All NIPT-positive cases were recommended to undergo invasive prenatal diagnosis.

Results: A total of 4736 participants received the NIPT test, including 2840 high-risk pregnancies, either with advanced maternal age or positive serum biochemical tests, and 1889 low-risk pregnancies without conventional indications; 99.9% (4732/4736) of the participants with a median maternal age of 35 years old received reports, and 1.3% (63/4732) were classified as test positive, including 36 T21, 19 T18, and 8 T13; 82.5% (52/63) took prenatal diagnosis, and 11.5% (6/52) false-positive cases were observed. The positive predictive values for the detection of T21, T18, and T13 were 94.4%, 79.0%, and 87.5%, respectively.

Conclusion: With stringent protocol, our prospective large-scale multicenter nationwide study demonstrated that NIPT showed excellent performance as screening tests for the detection of fetal T21, T18, and T13 in mixed-risk pregnancies in Thailand.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Chromosome Disorders / diagnosis*
  • Chromosomes, Human, Pair 13
  • Chromosomes, Human, Pair 18
  • Down Syndrome / diagnosis*
  • Female
  • Genetic Testing / methods
  • High-Throughput Nucleotide Sequencing / methods
  • Humans
  • Maternal Age
  • Middle Aged
  • Pregnancy
  • Pregnancy, High-Risk / blood
  • Prenatal Diagnosis / methods*
  • Retrospective Studies
  • Thailand
  • Trisomy / diagnosis*
  • Trisomy 13 Syndrome
  • Trisomy 18 Syndrome
  • Young Adult