The associations of nuchal translucency and fetal abnormalities; significance and implications

This review of literature describes the first-trimester nuchal translucency (NT) which forms the basis of new form of screening which can lead to a significant improvement in detection of congenital anomalies as compared to second trimester screening programs, the so called genetic-sonogram. A growing body of evidence-based studies has demonstrated that fetal NT can be a powerful prenatal screening tool and combined with first trimester serum markers, it can be incredibly promising in near future. It should be expressed as Multiple of median (MoM) and maintained and monitored like any laboratory analyte. The aim of this review was to investigate the different hypotheses on the aetiology of increased NT. Using a computerized database (PubMed), articles on the aetiology of first-trimester NT were retrieved. Furthermore, the cited references of the retrieved articles were used to find additional articles. Based on ultrasonography, the associations of increased NT fetuses are described in relation with Down syndrome, Cardiac anomalies, and a diverse range of other anomalies. The review concludes that first trimester NT ultrasound has the potential to be used as an important tool for the detection of various congenital abnormalities and an early management can be implemented to reduce the mental trauma of expecting mothers by proper counseling and early diagnosis. For the precise measurements, it should be implemented in a meticulous and coherent manner.