Changes in the lipid profile in pregnant women, with and without obesity, have been studied depending on the angiotensin-converting enzyme (ACE) gene I/ D polymorphism and the 4G5G polymorphism of the plasminogen activator inhibitor type I (PAI-1). The combination of the D-allele of the ACE gene and the 5G allele of the PAI-1 gene is a risk factor of increasing total cholesterol in pregnant women, regardless of the obesity class, and of increasing triglycerides in pregnant women without obesity. The presence of the D-allele of the ACE gene in the haplotype, regardless of the combinations of the genotypes of the PAI-1 gene, is a risk factor of increasing triglycerides in pregnant women with obesity.