Abstract The aim of study: Estimation of Polish population standards of the concentrations of pregnancy-associated plasma protein - A (PAPP-A) and free beta - human chorionic gonadotropin (β-HCG) in the maternal blood between 10.0 and 13.6 week of pregnancy and comparison of the biochemistry own normal ranges and literature reported data. Estimation the sensitivity of the fetal nuchal translucency measurement, biochemical concentrations of PAPP-A and free β-HCG in detection of the fetal chromosomal abnormalities. Material and methods: 582 women in the age 14 to 46 years old with singleton pregnancies were included to the study. The screening was performed between 10.0 and 13.6 week of gestation. The fetal nuchal translucency, serum concentrations of PAPP-A and free β-HCG were measured. The specific risk was calculated using the Fetal Medicine Foundation software (FTS) by accredited sonographers. Results: Standards for serum concentrations of PAPP-A and free β-HCG in normal pregnancies were determined. The measurement sensitivity of the fetal nuchal translucency in detection of the fetal chromosomal abnormalities was 80% and sensitivity of serum concentrations of PAPP-A and free β-HCG was 40% and 80%. Conclusions: There is no significant differences between estimated biochemistry standards (PAPP-A and free β-HCG) for Polish population and literature reported data. Observed differences in measurements of fetal NT, serum concentrations of PAPP-A and free β-HCG in a control group and the group with the aneuploidies confirmed usefulness of these methods for the first trimester prenatal screening.