[Long-term follow-up of children with increased nuchal translucency and normal karyotype]

The aim of this study was to investigate outcome at the age of two years for infants without known chromosomal anomalies who presented increased nuchal translucency (NT) at first trimester ultrasound examinations. One hundred fifty-one infants with NT measuring 3mm or more, between 12 and 16 weeks gestation, were followed for at least 24 months. A homogeneous pediatric examination was applied. Among these 151 infants, thirteen (8%) had a major isolated malformation. Five infants (3.3%) had chromosomal anomalies which were unrecognized on fetal karyotype owing to tissue mosaic in two and to cryptic chromosomal anomalies in three. At the age of two years, 16 children (10%) presented psychomotor retardation as part of a genetic syndrome, half of them had an associated cardiac malformation. We did not find any specific ultrasound characteristics which could be used to distinguish fetuses with impaired neurological prognosis. Newborns who presented NT at the first trimester ultrasound examination constitute a high risk population, particularly for psychomotor retardation which is not always recognized during the neonatal period. Careful pediatric follow up is required during childhood.