S Deidda

P09.19: Fetal loss and complications after genetic amniocentesis

Objectives: To evaluate the rate of preterm delivery (PTD) following late amniocentesis (>24 weeks of gestation). Methods: A retrospective cohort of all women with singleton pregnancy who underwent late amniocentesis in one tertiary center between 2005–2009, due to various indications, excluding cases of suspected amnionitis or premature rupture of membranes. Results: The initial cohort included 182 women. Pregnancy outcome was validated in 158 women who underwent amniocentesis at 24–36 weeks of gestation (mean, 31.4 ± 1.9). 13 women were excluded due to premature labor induction or cesarean section for suspected IUGR. Indications for late amniocentesis included abnormal ultrasonographic findings (n = 98), suspected intrauterine CMV or toxoplasmosis infection (n = 19), maternal age (n = 13), abnormal first or second trimester biochemical markers (n = 8) and others (n = 7). The rate of spontaneous PTD (<37 weeks) was 8.9% (13/145), mean gestational age at delivery 34.7 ± 1.3 (32–36 weeks). In only 5 (3.4%) delivery occurred ≤34 weeks of gestation. In one case (0.68%) of amniocentesis performed at 32 weeks of gestation, delivery occurred within 48 hours. In 4 cases (2.75%) delivery occurred within 10 day. The rate of PTD and mean gestational age at delivery stratified by grouped gestational age at amniocentesis is presented at Table 1. If cases of amniocentesis performed for ultrasonographic findings to rule out chromosomal abnormalities (n = 117/182), abnormal karyotype was found in 3 cases (2.56%). Conclusions: The risk of significant prematurity following late amniocentesis is low.

P16.06: Nuchal translucency and other US markers in cases of trisomy 18

(n = 134). Over a total of 134 fetuses with increased NT, karyotype was analysed in 129 cases (96,3%) and pregnancy outcome was available in 124 cases (92.5%). A chromosomal anomaly was detected in 57 fetuses (44.2%). In 72 (55.8%) fetuses, the karyotype was normal. The overall incidence of an adverse pregnancy outcome in the latter subset was 25% (18/72). Anomalies were detected, at the time of ultrasound, in 12 cases (16%) with 4 isolated cardiac defects and 8 other structural defects. Genetic syndromes occurred in 5 (6.9%) fetuses with normal karyotype. An adverse neonatal outcome was recorded in 1 case in which there were normal findings at the 20-week scan. Conclusion: After exclusion of chromosomal anomalies, 18/72 of the fetuses with increased NT had an adverse pregnancy outcome diagnosed in utero in 17/72 cases. Counselling should stress that, if the karyotype is normal and no fetal structural malformations were missed prenatally, a favourable outcome can be expected.

P26.21: Multiple congenital anomalies syndrome with urorectal septum malformation, absent radii, cerebellar vermis aplasia: case report

routine ultrasound. A bilateral renal disease with oligohydramnios was diagnosed in her first pregnancy and the baby was stillborn with Potter sequence. In the actual pregnancy the ultrasound done at 26 + 4 weeks of gestation showed right pyelocalicial and proximal ureteral dilatation with narrowing. In the neonatal period a 3D scan with multiplanar views demonstrated a megaureter associated with ureteral valve and a distal ureteral stenosis. The diagnosis was confirmed via surgical exploration and histology. While rare this might be a cause of ureteral obstruction with progressive upper tract dilatation. We emphasize the value of multiplanar 3D which allowed a diagnosis that only few years ago was privative of excretory urography.

P01.39: Experience on 1,282 cases of genetic amniocentesis: fetal loss and complications

Objective: The purpose of this study was to measure the fetal nasal bone between 11–14 weeks of gestation in order to elaborate a reference range for the Brazilian population. Methods: In this prospective and transversal study, crown-rump length, nuchal translucency, and nasal bone length were measured in 171 singleton pregnancies between 11 and 14 weeks of pregnancy. For statistical analysis the linear regression was used. Results: 171 singleton pregnancies which newborns had a normal phenotype were included in this study. A reference range of fetal nasal bone was elaborated. Median and percentiles 5 and 95 were also determined. The reference range was done after adjusting the coefficient of determination (R2) was 59.4% (p < 0.001). Conclusion: The length of the nasal bone showed a linear growth between 11–14 weeks of gestation.

P10.30: Low risk of fetal loss and complications following genetic amniocentesis: experience on 942 cases

Objective: To assess the visualization of fetal nasal bones in second trimester fetuses using antenatal 3D US and post-mortem CT and compare with standard 2D US. Methods: 4 fetuses with Down syndrome and absent nasal bone on 2D US and 6 fetuses with non-facial malformations were included in the study. In addition prenatal 3D US with maximal mode rendering was performed antenatally and compared with images of the bony face acquired from multidetector CT-scan and 3D volume rendering after pregnancy termination. Results: The 6 fetuses with normal chromosomes had on both 3D US and 3D CT bilateral NB. Three fetuses with Down syndrome had in both methods absent NB. One fetus with Down syndrome had one right absent nasal bone and a hypoplastic left nasal bone. This interesting finding was not recognized in 2D US, suspected in 3D US and confirmed in CT. Conclusions: 2D US gives limited information in suspected hypoplastic or absent NB. 3D US with maximal rendering is a reliable tool in assessing both right and left NB prenatally. Postmortem 3D CT is an impressive tool in confirming 3D prenatal rendering of skeletal findings.