EP18.29: First trimester screening at conditions of limited resources

We present own experience of two years of screening for chromosomal abnormalities in the first trimester under conditions of limited capacity due to military status. To assess the risk of chromosomal abnormalities in the fetus, we used the pregnant woman age, anamnesis, ultrasound markers. Biochemical studies were extremely limited due. The risks were calculated at the FMF software (2.8.1) without biochemical markers. During this period, 351 pregnant women were examined. There were 81 women aged 35 years and older(23.1%). The multiple pregnancies -8(2.3%). 99.7% of the women were Caucasian. Previous Tr. 21-1,1%. NT>3,5mm -1,1%, NT>95‰ –2,2%, NT<5‰ –1,7%. Abnormal NB– 0,8%. Abnormal TR–0,3%. Total PI DV–349, mean=-0,010, Std. dev.=0,0637. Anatomical abnormalities –1,95% (fetal edema, CNS, cardiac, abdominal wall, bone abnormalities, diaphragmal hernia). Based on the distribution of maternal age, it was expected that the study population contained 1.2 cases of Tr 21 and approximately the same number of other chromosomal abnormalities. The calculated risk was 1:100 or more in 4(1.1%) cases. These pregnant women underwent invasive PD or postnatal karyotype determination. Only 1 fetus (0.28%) with an enlarged NT(>3.5 mm) and multiple malformations, which was aborted at 13 weeks' gestation, had Tr18 determined postnatally. Other fetuses with identified anatomical anomalies did not have chromosomal abnormalities. All other pregnancies were no verified fetuses with Tr 21,13,18. In settings with limited capacity and resources (when both technical and time resources are limited), performing an ultrasound scan at 11 - 13 weeks together with risk assessment (without wasting time on additional visits and the impossibility of biochemical screening) significantly improves coverage and provides optimal information on risk groups to determine further management tactics. The calculations obtained in the surveyed population were adjusted to the postnatal results, i.e. we did not observe any missed cases of Tr 21, 13, 18 during the two years of the study.