P11.05: Fetal aneuploidy and structural abnormalities by a 11-14-week routine ultrasound scan in an unselected Serbian population

Abstract

A prospective observational cohort study of unselected pregnant women attending an 3D/4D abdominal and vaginal ultrasound examination in 11–14 weeks' gestation. Prenasal thickness, NT and jugular lymphatic sacs (JLS) as markers for aneuploidy. Morphological data revealed that nuchal edema is associated with jugular lymphatic distension. We used the multiplanar mode to obtain the exact mid-sagittal plane and measured the prenasal thickness as the shortest distance between the anterior edge of the lowest part of the frontal bone and the skin anteriorly. Out of 2824 pregnant women, 56 (2.0%) were found to have a missed abortion at the time of the ultrasound scan and 36 (1.3%) were diagnosed as twins. One case was occasionally diagnosed as a mola. 24 major structural abnormalities were detected, 2 cases of holoprosencephaly with hypothelorisam (one case also had a spina bifida), 1 case with hydranencephaly, 2 hydrocephalic fetuses, 2 cases with gastroschisis, 2 case with a bilateral hydronephrosis, 2 unilat. kidney agenesis, 1 megacistis, 2 osteogenesis imperfecta, 2 transposition of great vessels, 2 hypoplastic left ventricle, 1 stenosis A. pulmonalis with ASD, 4 case with a generalized hydrops and 1 fetus with multiple malformations. An additional number of 6 structural defects were detected at birth, including 2 polydactily and 4 non operative VSD. The antenatal ultrasound detection rate was 80% (24/30). Ten patients had a nuchal translucency greater than 3 mm; three of them had chromosomal abnormalities (trisomy 21, trisomy 18). Fetal structural abnormalities at a routine 11–14 weeks ultrasound scan for dating, in an unselected pregnant population, were detected in 80% of the cases. Three out of ten fetuses with a nuchal translucency greater than 3mm. and prenasal thickness and JLS was above the 95th centile had a chromosomal abnormality.