Fetal thickened nuchal soft tissues may first appear in the second trimester in Down syndrome

✍ Scribed by Etan Z. Zimmer; Shraga Blazer; Shai Linn; Moshe Bronshtein

• Book ID: 102332091
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 105 KB
• Volume: 38
• Category: Article
• ISSN: 0091-2751
• DOI: 10.1002/jcu.20638

✦ Synopsis

Abstract

Purpose.

To describe a series of cases of late‐onset fetal nuchal translucency in Down syndrome.

Method.

In our practice area, most pregnant women usually undergo 3 different sonographic examinations: a fetal nuchal translucency examination in the 1st trimester and 2 detailed surveys of all fetal organs in the early 2nd trimester and in midpregnancy.

Result.

During the study period (2003–2008), we detected 11 fetuses with new appearance of severe thickened nuchal soft tissues (≥6 mm) at 14–16 weeks' gestation after a normal nuchal screening in the 1st trimester. All of these fetuses had trisomy 21. Associated structural anomalies were observed in 10/11 of the cases. In addition, there were 12 fetuses with new appearance of thickened nuchal soft tissues (<4 mm); all these fetuses had a normal karyotype and were normal at delivery.

Conclusion.

Obstetricians should be aware that a nuchal abnormality may first appear only at 14–16 weeks' gestation. Fetal karyotyping is advocated in these cases because of the high probability of Down syndrome. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010