Long-term Outcome of Pregnancies with Increased Nuchal Translucency and Normal Karyotype

Abstract

The aim of this study was to examine the prevalence of major and minor anomalies according to the increase of NT thickness. Methods: This is a long-term retrospective study in which singleton gestations of euploid fetuses with increased NT were analyzed. NT measurement was performed in the first trimester examination according to the criteria of fetal medicine foundation (FMF) when the fetal crown-rump length (CRL) was 45 to 84 mm. The cases were followed up from 1 to 5 years postpartum to assess the presence of CHD and to point out other anomalies that could be associated with increased NT. Results: The outcome of 133 cases could be analysed out of 198 pregnancies of which in 55 cases some congenital anomalies (minor or major) were revealed up to the 5 years of life (prevalence of 41.4%). The prevalence of CHDs, including the defects of the great vessels, stood out among the others. In the group with NT between 95th and 99th centiles four cases with minor heart problems were identified (11.1%, 4/36). The rate of major cardiac defects proved to be 13.3% (6/45) in the group with NT between 3.5-4.4 mm, and 17.3% (9/52) in the group with NT > 4.5 mm. Among the 35 healthy children with various minor health problems not related to the presence of increased nuchal translucency there were 7 cases with hydrocele. In 3 of them it was associated with unilateral inguinal hernia but in 3 it was isolated and one was part of a complex malformation (The rate of other organ-specific anomalies did not prove to be significant). In the whole study population only thirteen cases (9.8%) ended up in intrauterine death, or arteficial abortion. Conclusion: The prevalence of major cardiac defects as well as other major anomalies increases with fetal nuchal thickness. Since the prevalence of CHD is 100 times higher in the population of fetuses with NT above 4.5 mm, specialist fetal echocardiography should be offered in the second trimester together with other follow-up investigations. Among the children without any major abnormalities, a high number of minor anomalies were revealed during the long-term follow-up. These anomalies do not have significant disadvantage to the quality of life, but some of them necessitates short or long-term medical treatment and this should also be leveled with the future parents. Despite the numerous investigations the exact etiology of increased NT remains unknown. The relatively high prevalence of hydrocele in the newborns in our material raises the question wheather it is related to the presence of NT in the fetal period because of abnormal lymphatic development or alterations in the extracellular matrix. Further long-term follow-up studies could probably contribute to find explanation on the etiology of increased NT in the first trimester. These data can be used when counseling parents of euploid fetuses with increased fetal NT.

Prenatal and Postnatal Echocardiography in Euploid Fetuses with Increased Nuchal Translucency

“…According to the results, the strongest correlation (60%) was observed between the diagnosis of a prenatal congenital heart defect and the thickness of 2.5 to 3.4 mm. The present results were consistent with the f indings of Orosz (2009), in which the prevalence of heart defects increased with NT enhancement. In line with our results, Saldanha (2009) reported that the prenatal heart defects and postnatal abnormalities are related to the NT thickness.…”

“…A congenital heart defect is the most frequent congenital malformation affecting 4% to 8% infants which is one of the main responsive factors for neonatal deaths in the f irst year of their life (Haak & van Vugt, 2003). Half of these malformations are asymptotes minor def icits and the other half are considered as major (Orosz , 2009;Galindo , 2003). It was revealed that prenatal diagnosis can be a very helpful and even life-saving option in case of def inite fetal heart def icits and other structural abnormalities (Becker & Wegner, 2006 approved as a sensitive parameter for the screening of chromosomal and heart defects in both chromosomally normal and abnormal fetuses (Orosz ., 2009;Galindo ., 2003).…”

“…It was revealed that prenatal diagnosis can be a very helpful and even life-saving option in case of def inite fetal heart def icits and other structural abnormalities (Becker & Wegner, 2006 approved as a sensitive parameter for the screening of chromosomal and heart defects in both chromosomally normal and abnormal fetuses (Orosz ., 2009;Galindo ., 2003). Several studies reported that euploid fetus with elevated NT is at a higher risk for a wide range of fetal structural defects, in particular, congenital heart defects as well as specif ic genetic syndromes (Orosz ., 2009;Galindo ., 2003;Barker Clur, 2010;Bilardo ., 1998Bilardo ., , 2007Clus ., 2008;Tahmasebpour ., 2012;Souka ., 2001Souka ., , 2005Lopes ., 2003 http://www.caves.res.in/ dysfunction, venous congestion in the head and neck, abnormal or delayed evolution of the lymphatic system, modif ied combination of the extracellular matrix, ly m p h a t i c d ra i n a ge f a i l u re, fe ta l a n e m i a o r hypoproteinemia, congenital infections, musculoskeletal abnormalities, and hormonal disorders (Orosz ., 2009;Saldanha ., 2009;Tahmasebpour ., 2012). Since the majority of fetuses with elevated NT and normal karyotype suffered from the congenital heart defect, a new high-risk group requiring fetal echocardiography has been def ined (Lopes ., 2003).…”

Euploid Fetuses With Increased Nuchal Translucency in Prenatal and Postnatal Follow Up

“…Lindsey et al, (2006) concluded 20 % of adverse pregnancy outcome in increased nuchal translucency euploid fetuses 15 . The overall rate of adverse pregnancy outcome was proportional to the degree of NT enlargement, ranging from 1.9 % to 64.7 % such as Bilardo et al, (2007) 20 . This difference can be due to 5 year postnatal follow up of cases.…”

Normal and Abnormal Early Pregnancy

“…60,61 Since the 1990s, extensive studies have established that euploid fetuses with increased nuchal translucency (NT) have a higher risk for a wide range of fetal structural defects, for specific genetic syndromes, and especially for congenital heart defects (CHD). 62,63 Severe CHDs with high probability of detection by EFE: D-and L-transposition of the great arteries (D-TGA, L-TGA) hypoplastic left heart syndrome (HLHS) based on aortic and mitral valve atresia or severe stenosis; atrioventricular septal defect (AVSD); double outlet right ventricle (DORV); common arterial trunk (CAT); double inlet left ventricle (DILV); tricuspid atresia (TA); mitral atresia (MA); pulmonary atresia (PA); heterotaxy syndromes; total anomalous pulmonary venous return (TAPVR); large ventricular septal defects (VSD).…”