First-trimester examination of fetal nasal bone in the Chinese population

• Published in: Prenatal diagnosis Vol. 26; no. 8; pp. 703 - 706
• Main Authors: Chen, Min, Lee, Chin Peng, Tang, Rebecca, Chan, Ben, Ou, Chun Quan, Tang, Mary Hoi Yin
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-08-2006; Wiley
• Subjects: Adolescent; Adult; Biological and medical sciences; China; Female; Fetal Development; fetus; first trimester; Gynecology. Andrology. Obstetrics; Humans; Management. Prenatal diagnosis; Medical sciences; Nasal Bone - diagnostic imaging; Nasal Bone - embryology; nasal bones; Pregnancy; Pregnancy Trimester, First; Pregnancy. Fetus. Placenta; prenatal diagnosis; Reference Values; ultrasonography; Ultrasonography, Prenatal - methods; Asia; China; Sonography; Pregnancy; Human; ultrasonography; Prenatal Diagnosis; Echography; Nasal bone; nasal bones; Chinese; Fetus; First trimester
• ISSN: 0197-3851; 1097-0223
• DOI: 10.1002/pd.1484

Objectives
Absence of the nasal bone in fetuses with trisomy 21 is a potential ultrasound marker for Down syndrome from the first trimester onwards. Racial differences in fetal nasal bone length have been reported. There was no reference range for the first‐trimester fetal nasal bone length (NBL) in the Chinese population.
Methods
From January 2002 to February 2005, we investigated the reference range of NBL in 2169 singleton fetuses whose parents were Chinese with normal pregnancy outcome. Ultrasound measurements of NBL were performed on a midsagittal plane at 12–14 weeks' gestation.
Results
The nasal bone length measurement showed a significant increase with gestational age (GA) (p < 0.05). A linear relationship between nasal bone length and gestational age (NBL = −3.3462 × GA + 0.627, R2 = 0.30, p < 0.001) as well as a linear relationship between nasal bone length and crown‐rump length (CRL) (NBL = 0.3741 × CRL + 0.284, R2 = 0.30, P < 0.001) was established.
Conclusion
The measurement of nasal bone length was feasible in the first trimester. The reference range of NBL in normal Chinese fetuses in the first‐trimester of pregnancy was established. This formed a basis for further study on the use of fetal nasal bone measurement in the screening for aneuploidy in the Chinese population. Copyright © 2006 John Wiley & Sons, Ltd.