Introduction. a composition of seminal plasma reflects a state of reproductive organs that are involved in sperm production.
Aim: to study a concentration of fatty acid-binding protein (FABP) in blood serum and sperm samples with normal and altered characteristics.
Materials and methods: a total of 82 men with mean age of 33.1±4.7 years old who were examined to clarify the cause of infertility were included in the study. The main group (n=21) consisted of men with oligozoospermia, while control group (n=33) consisted of healthy men with normal sperm analysis. In addition, patients with high viscosity of sperm were included in the comparison group (n=28). There were no changes in complete blood count and biochemical blood panel in all participants. The content of FABP in blood serum and seminal plasma was determined.
Results: the average content of FABP in seminal plasma was 1.347±0.26 ng/ml and exceeded the serum concentration of this compound (p<0.000001), which was 0.305±0.193 ng/ml. The concentration in seminal plasma did not depend on its serum concentration (R=0,068194), as well as the sperm volume and viscosity, but it was correlated with sperm concentration (R=0,66387). The concentration of FABP in seminal plasma was highest in the control group (1.47±0.33 ng / ml) and it was higher compared to the main group (1.22±0.09 ng/ml; p=0.000057) and the comparison group (1.29±0.19 ng/ml; p=0.010822). There was no difference between groups in serum concentration of FABP
(p=0.9814).
Conclusion: the obtained data suggest that a reduced level of FABP in seminal plasma can be considered as unfavorable criterion indicating a reduced fertility.

Keywords: oligoasthenozoospermia, fatty acid-binding protein, seminal plasma, sperm