Virtual poster abstracts which a fetal growth scan was performed at 34 +0/7 to 37 +0/7 weeks of gestation. Composite adverse neonatal outcome at discharge was defined by the presence of at least one of the following: birthweight >4,000 g, neonatal hypoglycemia requiring glucose 5% intravenous infusion, and shoulder dystocia not resolved by McRoberts' manoeuvre. Results: Population: 225. Characteristics of pregnancies with normal or adverse neonatal outcome at discharge are shown in table 1 (median values are reported). Binary logistic regression showed that ultrasound estimated fetal weight Z score (adjusted odds ratio (aOR) 6.82; p < 0.0001) and 1-hour maternal glucose level (aOR 1.02; p = 0.027) were associated with adverse neonatal outcomes. Conclusions: Estimated fetal weight at 34

The aim of the study was to evaluate the changes in diagnostics of Trisomy 21 in a 10 mil population between 1994-2018. Methods: Data from the national registries. Results: There were 5496 fetuses with trisomy 21 in the studied period. The detection rate increased from 40.7% (1994) to 87.66 (2018). The number of invasive procedures varied between 1757.6/10000 newborns (2007) and 580.9/10000 newborns (2018). Indications for invasive testing were 80% combined first-trimester screening (FTS) and 20% morphologic findings on ultrasound and second-trimester screening. The number of trisomy 21 newborns per 10000 decreased from 7.79 in 1994 to 3.42 in 2018. The gestational age at the final diagnosis decreased from 20.33 weeks in 1994 to 14.24 weeks in 2018. Since 2015, 122 cases of Trisomy 21 were detected with NIPT. Conclusions: Since 1994 the screening methods developed to FTS and NIPT. The Trisomy 21 screening has already in 2006 reached a plateau: the percentage of detected cases in the whole population exceeded 80% and was improving until 2020 to 87.6%. High sensitivity and specificity of FTS caused a steep decrease in invasive procedures. In the same time period, the maternal age was significantly increased without affecting the detection rates. We could not assess the effect of NIPT due to the small number of examinations. It can not be expected, that in real life, higher detection rates would be achieved in the whole population, even with new, more sensitive technologies. Research grant provided by the Czech Ministry of Health AZV17-29622A and RVO-VFN64165.

Electronic poster abstractswith a birthweight

Objectives:The uterine activity separated from maternal abdominal signal could contribute to better diagnosing of threatened preterm birth. This signal is being obtained via equipment for fetal non-invasive electrocardiography. The detection of acceleration capacity (AC) and deceleration capacity (DC) variables reflects the fetal neurological development. Methods: Totally examined 192 pregnant women. The US cervicometry was performed at 16 weeks of gestation. The patients with normal cervical length (> 30 mm) were enrolled in Group I (n = 34). The US investigation of cervical length and fetal AC/DC detection via transabdominal non-invasive electrocardiography at 26, 32, and 38 weeks of gestation were used in Group II (n = 84). The investigation of uterine activity was additionally performed in women in Group III (n = 74). Fetal cardio signals and maternal uterine activity were obtained via non-invasive fetal electrocardiography using Cardiolab Babycard equipment (the ''KhAI Medica'' Scientific Research centre, Ukraine). The monitoring of fetal AC/DC was also performed in Group I. The results were analysed with an ANOVA test. Results:The level of AC/DC was minimal in all groups at 26 weeks. This fact reflects the immaturity of autonomic regulation. But later on, the decreased values of AC/DC were found in Group II and Group III at 32 and 38 weeks of gestation. Thus, the threatened preterm delivery has a negative projection on fetal neurodevelopment. The sensitivity and the specificity of the threatened preterm labour detection were in Group II and Group III respectively: 86.49% (95% CI -76.55% to 93.32%) and 58.82% (95% CI -40.70% to 75.35%); 98.46% (95% CI -91.72% to 99.96%) and 90.91% (95 % CI -58.72% to 99.77%). The use of uterine activity has improved the accuracy of threatened preterm labour diagnosing. Conclusions: The application of uterine activity extracted from electrophysiological maternal abdominal signal contributed to better diagnosing of the threatened preterm labour. Fetal neurodevelopment is retarded in case of the threatened preterm birth. VP24.05 Prenatal diagnosis and postnatal pathohistological verification of mature teratoma

Electronic poster abstractsResults: There is a significant association between growth restriction & MCA PI1 with a sensitivity of the MCA PI1 of 52% & specificity of 100%. 12 true negatives were correctly identified, with a positive predictive value of 100% & negative predictive value of 84% as there were cases that resulted into no growth. Accuracy is 86.7%. Out of the 90 test outcomes, 78 of them were the correct result. MCA PI2 after 2 weeks showed that out of the 90 subjects, 18 had abnormal/ positive test with no interval growth. 7 showed no interval growth, but with within normal/negative MCA PI. 65 subjects with normal MCA PI1 and with interval growth showed the same results for MCA PI2 on follow up. MCA PI2 has a sensitivity of 72%, specificity of 100%, positive predictive value of 100% and negative predictive value of 72%. Accuracy is 92.2%. Out of the 90 test outcomes, 7 did not show the correct result. Conclusions: MCA Doppler is a useful tool in helping us make a diagnosis of IUGR among high risk pregnant women at 28-38 weeks. There is a a significant association between MCA PI and interval growth, thus helping us classify the small for gestational age babies into the truly growth restricted and the constitutionally small for age. MCA on initial visit has an accuracy of 86.7%; helping us institute already the necessary management for these cases. EP19.20 Systolic and diastolic aortic isthmus (AoI) components