Laboratory examination methods in pregnancy focused on screening of congenital malformations in the fetus

In my bachelor´s thesis, I deal with screening examination methods in pregnancy, focusing on revealing the risk of congenital developmental anomalies. It is a complex of examinations combining the laboratory determination of biochemical markers in the maternal serum with parameters of ultrasound screening. In the first and early stages of the second trimester the plasmatic protein A and a free beta sub-unit of chorio gonadotropin is examined. The examination is combined with the ultrasound examination of nuchal translucency. In the second trimester of pregnancy, most often in the 15-17th weeks of the pregnancy it consists of the determination of alfa- fetoprotein and choriogonadotropin, sometimes moreover with the non-conjugated estriol. In the laboratory of the clinical biochemistry Privamed of the Municipal Hospital in Plzeň I measured 60 samples of maternity serum for screening in the first trimester and 60 samples for screening in the second trimester on the Roche Elecsys 2010 appliance. I evaluated all the samples in the co-operation with the laboratory for Genetics Plzeň s.r.o. in Alpha software, processing the entered values of biochemical markers, the values measured by the ultrasound and the clinical data of the patient. Out of 60 samples for the first trimester screening, 2 were positive for trisomy of the 21st chromosome and 1 for trisomy of the 18th chromosome, the remaining 57 were negative. Out of 60 for screening in the second trimester, 3 samples were positive for trisomy of the 21st chromosome and 2 for the defects of the neural tube. The positive screening, however, does not mean the presence of the defect, only the increased risk of occurrence. The woman with the positive result of screening are being offered mostly one of the methods of the prenatal diagnostics, for the performance of which taking the amniotic fluid or chorionic villus is necessary, which is invasive for the woman. Prenatal diagnostics focuses first of all on the determining the karyotype of foetus