Perinatology.  2019 Jun;30(2):78-82. 10.14734/PN.2019.30.2.78.

Chromosomal Abnormalities in Korean Fetuses with Nuchal Translucency above the 99th Percentile

• Kwak DW
• Boo H
• Chang EH
• Ryu HM
• Han YJ
• Chung JH
• Kim MY
• Yang EJ
• Yoo HJ
• Kim JW

• KMID: 2453042
• DOI: http://doi.org/10.14734/PN.2019.30.2.78

Abstract

OBJECTIVE
To evaluate the prevalence and distribution of chromosomal defects in Korean fetuses with nuchal translucency (NT) above the 99th percentile and to analyze them according to the degree of NT thickness.
METHODS
This study retrospectively reviewed the medical records and ultrasonography images of pregnant women whose fetuses were diagnosed with NT ≥3.5 mm at 11 to 14 weeks of gestation and who underwent karyotyping between 2009 and 2015 at Cheil General Hospital, Seoul, Korea.
RESULTS
Among 514 fetuses that met the inclusion criteria, 198 (38.5%) fetuses were confirmed as having chromosomal defects. 156 (30.4%) fetuses concerned autosomal aneuploidies, 27 (5.3%) sex-chromosome aneuploidies, and 1 (0.2%) triploidy. Besides, 11 fetuses (2.1%) were identified as pathogenic structural unbalanced chromosome aberration. When the study populations were divided based on NT thickness, 19.8% fetuses with a thickness of 3.5-4.4 mm, 33.0% of 4.5-5.4 mm, 50.3% of 5.5-6.4 mm, and 67.2% of 6.5 mm or more had chromosomal defects.
CONCLUSION
The incidence of chromosomal abnormalities of Korean fetuses with NT thickness above 99th percentile increases with NT thickness, and the prevalence and distribution based on NT thickness were very similar to those of Caucasian fetuses in previous reports.

Keyword

Aneuploidy; Pregnancy trimester; first; Nuchal translucency measurement; Karyotyping

MeSH Terms

Aneuploidy
Chromosome Aberrations*
Female
Fetus*
Hospitals, General
Humans
Incidence
Karyotyping
Korea
Medical Records
Nuchal Translucency Measurement*
Pregnancy
Pregnancy Trimesters
Pregnant Women
Prevalence
Retrospective Studies
Seoul
Triploidy
Ultrasonography

Reference

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