Possibilities for prediction of congenital fetal malformations and chromosomal abnormalities based on the determination of the levels of free amino acids and their nitrogen-containing derivatives in blood plasma of pregnant women

Abstract

Objective: to determine the possibilities for prediction and diagnosis of congenital fetal malformations and chromosomal abnormalities on the basis of the study of the levels of amino acids and their nitrogen-containing derivatives in blood plasma of pregnant women with pathological conditions requiring artificial termination of pregnancy. Material and methods. The content of free amino acids and their nitrogen-containing derivatives was studied in 104 pregnant women having congenital malformations and chromosomal abnormalities in their fetuses at 13-22 weeks` gestation (group I) and 25 women with physiological pregnancy (group II). The amino acid level was determined by the high-performance liquid chromatography method. Results. The levels of 14 out of the 26 studied amino acids in the blood plasma of the pregnant women of group I were statistically higher than those of the women in group II. ROC analysis was used to determine six amino acids (glycine, α-aminobutyric acid, hydroxylysine, glutamic acid, citrulline, serine) and their threshold values which with high accuracy (85.3 %) allow of predicting congenital fetal malformations and chromosomal abnormalities. A prognostic model making it possible to determine high probability of congenital fetal anomalies based on the determination of the concentration of 5-hydroxytryptophan, glycine, asparagine, and serine in blood plasma of pregnant women has been developed. Conclusion. The study of the levels of amino acids and their nitrogen-containing derivatives in plasma of pregnant women at 13-22 weeks` gestation can be used for prenatal diagnosis of congenital fetal malformations and chromosomal abnormalities, as well as used as an additional criterion for making the decision on the necessity for artificial termination of pregnancy upon fetal medical indications.