Threshold of nuchal translucency for the detection of chromosomal aberration: comparison of different cut-offs.
This study evaluated the sensitivities and false positive rates of the screening test using ultrasonographic measurement of thickness of nuchal translucency (NT) with different cut-offs for chromosomal aberration in a Korean population. We included 2,570 singleton pregnancies undergoing ultrasound between 11 weeks and 14 weeks of gestation in this study. We analyzed the sensitivities of NT alone for screening chromosomal aberration using three cut-offs -2.5 mm, 3.0 mm, and 95th percentile for each crown rump length (CRL). There were 31 chromosomal aberrations (1.2%) including 12 cases of trisomy 21. The numbers of chromosomal aberrations that were detected by NT with different cut-offs of 2.5 mm, 3.0 mm and the 95th percentile CRL were 22, 18 and 23, respectively. At a threshold of 2.5 mm, the sensitivity and the false positive rate for total chromosomal aberrations were 67.7% and 6.3%, respectively. At 3.0 mm, those were 54.8% and 3.5%, respectively. At the 95th percentile CRL, those were 70.9% and 5.8%, respectively. The use of CRL-dependent cut-offs for nuchal translucency improves the detection of chromosomal aberrations when compared to fixed cut-offs in a Korean population.
Department of Obstetrics and Gynecology, Samsung Cheil Hospital and Women's Healthcare Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Min-Hyoung
MH
Kim
Su-Hyun
SH
Park
Hye-Jin
HJ
Cho
June-Seek
JS
Choi
Joo-Oh
JO
Kim
Hyun-Kyong
HK
Ahn
Joong-Sik
JS
Shin
Jung-Yeol
JY
Han
Moon-Young
MY
Kim
Jae-Hyug
JH
Yang
D000328:Adult; D002869:Chromosome Aberrations; D025063:Chromosome Disorders / Q000175:diagnosis; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000235:genetics; D006801:Humans; D008403:Mass Screening / Q000379:methods; D048208:Nuchal Translucency Measurement / Q000379:methods*; D011247:Pregnancy; D012680:Sensitivity and Specificity