First-trimester screening for Down syndrome; the role of nasal bone assessment in the Korean population

• Published in: Prenatal diagnosis 2007-09, Vol.27 (9), p.830-834
• Main Authors: Moon, Min Hoan, Cho, Jeong Yeon, Lee, Yu Mi, Jung, Sung Il, Yang, Jae Hyug, Kim, Moon Young, Ryu, Hyun-Mee, Chung, Jin Hoon, Park, Seong Ho
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Down Syndrome - diagnosis; ethnicity; Female; first trimester; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; Gynecology. Andrology. Obstetrics; Humans; Korea; Management. Prenatal diagnosis; Medical sciences; Molecular and cellular biology; nasal bone; Nasal Bone - anatomy & histology; Nasal Bone - diagnostic imaging; Nasal Bone - embryology; Pregnancy; Pregnancy Trimester, First; Pregnancy. Fetus. Placenta; Prospective Studies; trisomy 21; Ultrasonography, Prenatal; ultrasound
• ISSN: 0197-3851; 1097-0223
• DOI: 10.1002/pd.1785

Objectives The aim of this study was to evaluate the role of nasal bone assessment in first‐trimester screening for Down syndrome (DS) in the Korean population. Methods From July 2004 to March 2006, we prospectively evaluated the fetal nasal bones at 11–14 weeks' gestation in the Korean population. Results A successful evaluation was possible in 6490 of 6787 fetuses (95.6%). Absent, hypoechoic, and short nasal bones were seen in 4 (26.7%), 4 (26.7%), and 1 (6.7%) of 15 fetuses with DS, respectively, whereas in 5 (0.1%), 11 (0.2%), and 246 (3.8%) of 6456 normal fetuses. The incidence of absent and hypoechoic nasal bone showed significant differences between normal fetuses and fetuses with DS (P < 0.0005, both). Screening for DS using an absent or hypoechoic nasal bone resulted in a sensitivity of 53.3%, a specificity of 99.8%, a positive likelihood ratio of 215.2, and a negative likelihood ratio of 0.5. Conclusion Our study showed that nasal bone abnormality at 11–14 weeks of gestation had a high association with DS in the Korean population. This suggests that nasal bone assessment can be used to supplement the current first‐trimester screening for DS in the Korean population. Copyright © 2007 John Wiley & Sons, Ltd.