Background: The study of the insufficient fetal growth causes remains one of the priorities in modern obstetrics. In the absence of widely recognised maternal risk factors, genetic determinants of antenatal developmental disorders are particularly important in providing a modern, promising approach to diagnosing and understanding the pathogenesis of the pathology. The aim of the study: To study the associations between different polymorphisms of the AQP1 gene and the clinical manifestations of foetal growth restriction (FGR). Materials and methods: The study included 147 pregnant women whose pregnancies were complicated by insufficient fetal growth. They were divided into two subgroups: subgroup Ia comprised patients with antenatally diagnosed fetal growth restriction (n=80), and subgroup Ib included patients whose pregnancies resulted in the development of a small-for-gestational-age (SGA) fetus (n=67). The control group consisted of 150 women whose pregnancies culminated in the birth of infants with normal anthropometric parameters. All participants underwent genotyping using MALDI-TOF mass spectrometry on the Sequenom MassARRAY4 platform. Results: For the first time, an association of rs10253374 and rs4723022 of the AQP1 gene with the development of FGR was identified. The CC genotype of rs10253374 was found to confer an increased risk (OR=2,210; p = 0.015), while the AA genotype of rs4723022 was also associated with an elevated risk (OR=2,261; p = 0.026). Genotypic combinations turned out to be informative for identifying both risky combinations of genotypes (CC rs10253374 and AA rs4723022) and those with protective properties (TC rs10253374 and GA rs4723022) in relation to the FGR development. No significant associations were found between polymorphic markers of the AQP1 gene and SGA. The association analysis of the studied AQP1 gene polymorphic loci with clinical and laboratory data revealed the following: in the control group, during combined first-trimester prenatal screening, the rs4723022 locus was associated with the fetal growth retardation risk value calculated in the Astraia software. The highest risk value (637) was observed for carriers of the GA genotype. In the main group of patients whose previous pregnancy was complicated by insufficient fetal growth, the AA genotype was found in 100% of cases. Conclusion: The obtained data suggest that the investigated polymorphisms of AQP1 gene may play a certain role in the FGR development. Further studies with larger cohorts are needed to replicate these results, along with the application of advanced functional genomics approaches to elucidate the role of AQP1 in the etiopathogenesis of FGR