L. Novac

Improved detection rate of structural abnormalities in the first trimester using an extended examination protocol

To assess the potential of first‐trimester sonography in the detection of fetal abnormalities using an extended protocol that is achievable with reasonable resources of time, personnel and ultrasound equipment.

First trimester two‐ and four‐dimensional cardiac scan: intra‐ and interobserver agreement, comparison between methods and benefits of color Doppler technique

To evaluate intra‐ and interobserver agreement for first‐trimester fetal cardiac structural assessment, using two‐dimensional (2D) ultrasound (2D‐US) and 4D‐US (4D spatiotemporal image correlation (STIC) technology), to compare the methods and to assess the advantages of adding color Doppler to each technique.

Agenesis of ductus venosus in sequential first and second trimester screening

The goal of this study is to evaluate the potential of first trimester (FT) screening in the diagnosis of agenesis of the ductus venosus (ADV) and to study its prevalence in a low‐risk population, the associated conditions, and pregnancy outcome.

P25.03: Relation between nuchal translucency thickness and prevalence of chromosomal defects, miscarriage, fetal death and major fetal abnormalities

Objective: To determine whether Doppler velocimetry of the ductus venosus can improve the predictive capacity of increased nuchal translucency in the detection of trisomy 21 at 11–14 weeks of gestation. Methods: Ductus venosus Doppler ultrasound blood velocity waveforms were obtained prospectively at 11–14 weeks of gestation in 2280 consecutive singleton pregnancies. Waveforms were classified either as normal in the presence of a positive A-wave, or as abnormal if the A-wave was absent or negative. All cases were screened for chromosomal defects by a combination of maternal age and fetal nuchal translucency thickness. Concerm TN, a Down sindromy was suspected when the nuchal translucency was above the 95th centile. In 344 cases karyotyping was performed. Results: Down syndrome was found in 37 cases. On basis in the NT the overall detection rate, specificity, positive predictive value, negative predictive value and likelihood ratio for trisomy 21 were 85.7%, 97.1%, 99.9%, 28% and 44.9% respectively. On basis in the ductus venosus blood flow during atrial contraction the sensitivity, specificity, the negative and positive predictive values and likelihood ratio were 82.9%, 98.8%, 99.7%, 56.9%, 69% respectively. Conclusions: Enlarged nuchal translucency and abnormal ductus venosus blood flow are useful markers of trisomy 21 in the first trimester ultrasound screening, assessment of ductus venosus blood flow velocimetry could improve the predictive for the detection of Down syndrome.

OC05.01: Reliability of first trimester structural sonographic extended evaluation

J. Degenhardt1, R. Schürg2, A. Kawecki3, M. Pawlik1, C. Enzensberger1, R. Stressig4, R. Axt-Fliedner1, T. Kohl3 1Division of Prenatal Medicine, University of Giessen and Marburg, Giessen, Germany; 2Department of Anesthesiology, University of Giessen and Marburg, Giessen, Germany; 3German Center for Fetal Surgery & Minimally Invasive Therapy, University of Giessen and Marburg, Giessen, Germany; 4University Hospital of Bonn, Bonn, Germany

OC12.04: Efficiency and repeatability of recently described markers of early neurosonogram

Objectives: Screening at 11–14 weeks is changing from a simple NT measurement to a comprehensive first trimester anomaly scan. However, the detection of open neural tube defect (NTD) before 14 weeks is still a challenge, since lemon and banana signs, used in second trimester ultrasound, are rarely present. Aim of the study is to seek for simple first trimester signs to alert the examiner for the presence of NTD. Methods: The midsagittal view of the face used for NT and nasal bone measurements was analyzed in normal fetuses and fetuses with NTD. The region between the brain stem and occipital bone, includes the 4th ventricle (intracranial translucency = IT), the choroid plexus of the 4th ventricle and the future cisterna magna. Results: In normal fetuses between 11–14 weeks there is an increase in the anterior posterior diameters of posterior fossa structures. Fetuses with NTD detected prospectively and retrospectively showed however abnormal values due to the downward shifting of the brain stem. Conclusions: In the plane used for NT measurement the evaluation of the posterior part of the brain between the brain stem and the occipital bone appears to be the clue in suspecting NTD at the 11–14 weeks scan. Further prospective studies are needed to find the sensitivity of these observations during routine screening.

P04.15: Correlations between trophoblast thickness and spontaneous abortion—statistical study

Objectives: Beta-thalassemia is the commonest genetic disorder in Egypt with an estimated carrier rate of 9–10%. The aim of the study was to look at the common mutations found in our population and the impact of prenatal diagnosis on parents attitudes. Methods: Prospective analysis of cases referred for prenatal diagnosis of thalassemia at Fetal Medicine Unit, Cairo University from 2007 till 2010. Families with previous affected child had molecular assessment of their mutations as well as in the affected siblings. In future pregnancies they would be referred for invasive testing at 11–12 weeks where chorionic villous samples (CVS) were obtained or amniocentesis samples were taken for those who show at later gestations. All cases would first undergo a detailed first trimester scan including assessment of risk for chromosome abnormalities using Medison Accuvix XQ machine (Korea). Samples were analyzed for point mutations using PCR reversed hybridization techniques, in cases with absence of mutant primers direct automated DNA sequencing is performed to located the uncharacterized DNA mutation. Patients with anomalies or high risk for chromosome abnormalities are counselled for fetal karyotype accordingly. Results: Forty one cases were sampled of which 28 cases were CVS and 13 were amniocentesis. Commonest mutations seen were IVS 110, IVS 1-6, IVS 1-1. Other mutations found were IVS 2-1, IVS 2848, IVS 2-745, Codon 5, 30, 39, 27, 87, some were uncharacterized. 13 cases were affected, 5 were normal and 23 cases were carriers. Nearly half of the affected cases were homozygous and other half were compound heterozygous. No miscarriages due to procedures occurred and 1 CVS case was repeated due to inadequate sample. Conclusions: Premarital counselling and couple screening is available but under-utilized. The availability of prenatal diagnosis service changed the current attitude of couples. The hope for bone marrow transplantation seems promising from normal siblings in carrier families.

OP15.01: Only one 13–15 weeks scan ‐ efficiency in low risk pregnancy

Objectives: To compare the effects of maternal hyperoxygenation on the Doppler waveforms in twin pregnancies where one fetus has IUGR and absent or reversed end diastolic flow (ARED) in room air. Methods: Women with monochorionic diamniotic twin pregnancies with one IUGR fetus with ARED in room air between 2006 and 2008 who were hospitalized after 24 weeks gestation for close surveillance and bed rest were included in the study. All fetuses had structurally normal hearts. None had evidence of twin-twin transfusion syndrome. Measurements of Doppler flow pattern in middle cerebral artery (MCA), free loop of umbilical artery (FLUA) and ductus venosus (DV) were made in room air and then after breathing 60% oxygen by face mask for twenty minutes. Results: Seven twin pregnancies were included. The normal cotwin in each case had normal Doppler waveforms in room air and oxygen. All seven IUGR fetuses had ARED in room air and dilated DV size. In five patients, the FLUA normalized (PI < 1.75) after breathing 60% oxygen (mean PI = 3.21 in room air versus mean PI = 1.65 in oxygen). These five patients who had positive change with oxygen delivered an average of 5 weeks (range 3–14 weeks) after hospitalization. The other two patients who had no change in FLUA with oxygen and had abnormal MCA and DV in room air were delivered for obstetric indications within one day of the test. Conclusions: Maternal hyperoxygenation may be associated with normalization of the FLUA in fetuses with ARED after 24 weeks of gestation. A positive maternal hyperoxygenation test can select IUGR fetuses who have an abnormal FLUA in room air with a better prognosis and may be useful in postponing delivery in these fetuses with ARED.

OP15.07: Benefits of early screening in fetal anomalies diagnosis

Cochrane meta-analysis about routine third trimester ultrasound included ultrasound of the 70’s and 80’s and no studies were really designed to answer that question. An adequate and contemporary trial would be needed. With a prospective study to describe practices, we aimed to evaluate the feasibility of a randomized trial. Methods: All women (n = 335) with a singleton foetus managed in our tertiary center since the beginning of their pregnancy and who delivered after 28 weeks were included prospectively over a 50-day period. Data about maternal characteristics, management of pregnancy and delivery, ultrasound practices and results were recorded. One hundred women had a brief personal interview to define their expectation and experience about third trimester ultrasound. Results: Women had 2.9 + / − 1.2 ultrasound scan during their pregnancy. All had a second trimester ultrasound and 53.7% had a third trimester ultrasound, without medical indication in 12.8%. Among ‘‘low-risk’’ pregnancy, 40% had a third trimester ultrasound. Of those, 21.6% were done for no medical indication. Among women interviewed who had a third trimester ultrasound scan, only 13.7% declared that this exam was stressful. Three quarter of the population interviewed would agree to join in a future trial. Conclusions: In our hospital, more than half of pregnant women had a third trimester ultrasound and this was not perceived as stressful. The recruitment for a randomized trial to evaluate the impact of routine third trimester scan on perinatal morbi-mortality in a lowrisk population will necessitate a multi-center collaboration as the sample size required is large. Until such trial is published, knowing that pregnant women will receive more than one ultrasound, health care resources should be planned for accordingly.