Premature delivery results from multiple factors - inflamation belongs to most important. Tumor necrosis factor (TNF)-alpha is a cytokine with pleiotropic biological effects and plays a role in inflamatory reactions. TNF-alpha level, which is influenced by genetic polymorphisms, was correlated with susceptibility to intra-amniotic infection (IAI). We have investigated -163G/A, -238G/A, -308G/A, -376G/A mutations of TNF-alpha gene in the group of women with IAI. Allelic frequency analysis have shown overrepresentation of -238A and -308A alleles in the IAI group (19.8% vs. 10.6%, O.R. = 3.0, p = 0.002 and 31.1% vs. 18.7%, O.R. = 1.97, p = 0.01, respectively). We could conclude that the presence of the -238A and -308A TNF-alpha point mutations play a role in the modulation of immunological answer in IAI.