P16.07: Screening for fetal aneuploidy and major abnormalities at 11–13 weeks' gestation, local particularities

Abstract

Chromosomal and structural anomalies screening at 11-13 weeks' gestation has grown rapidly in the last decade and now has an importance in prenatal consultation. To evaluate the results of this screening, according to local practice. Retrospective study of cases evaluated in 2009-2016. Were included in the study live, singleton pregnancies, with a Crown–rump length of 45–84 mm, which were evaluated for aneuploidy risk and major fetal abnormalities. 1362 patients were evaluated, the majority (99.9%) being Caucasian. 21% of them had an age ≥35 years. 33 (2.4%) of cases had a nuchal translucency> 3.5 mm. beta-hCG and PAPPA screening was associated in 964 (70.7%) of cases. Nasal bone was present on 1223 (90%) and absent in 27 (2%) of cases. The flow on tricuspid valve was normal on 1290 (94%), regurgitation being present in 18 (1.3%) cases. Ductus venous had an average pulsatility index of 1.09 ± 0.17 (mean ± standard deviation). There were 91 invasive diagnostic manoeuvres, and of these, 70 (77%) were chorionic villus biopsy. In 24 of them (26%) of chromosomal abnormalities have been identified: 12 (50%) trisomies 21, 6 (25%) sex chromosome abnormalities, the remainder being triploidies and Trisomy 18. 39 fetuses 18 (2.8%) had different types of structural anomalies: acrania, holoprosencephaly, ventriculomegaly, cleft lip / palate, diaphragmatic hernia, omphalocele, gastroschisis, megacystis, limb abnormalities and hydrops. At this gestational age, we found 17 cases (1.2%) with major heart defects. Ultrasound screening at 11-13 weeks is a feasible and effective method to detect chromosomal abnormalities and fetal structural low-risk pregnancies.