AimTo ascertain the incidence of respiratory tract colonization in extremely low gestational age newborns (ELGANs) withUreaplasma parvumandUreaplasma urealyticumand determine if there is a difference in the severity of bronchopulmonary dysplasia (BPD) between ELGANs with and withoutUreaplasmaspecies (spp) colonization.MethodsWe reviewed the medical records of ELGANs 23 0/7–27 6/7 weeks of gestation, tested forU. parvumandU. urealyticumin our Center from January 1, 2009 to December 31, 2019.Ureaplasmaspp were identified with the Mycofast Screening Revolution assay based on liquid broth cultures or with polymerase chain reaction.ResultsThis study enrolled 196 preterm newborns. Fifty (25.5%) newborns hadUreaplasmaspp respiratory tract colonization, withU. parvumbeing the predominant species. The incidence rate of respiratory tract colonization withUreaplasmaspp slightly increased in the studied period. The incidence rate for 2019 was 16.2 per 100 infants. BPD severity significantly correlated withUreaplasmaspp colonization (P= 0.041). After controlling for other risk factors for BPD in a regression model, preterm infants colonized withUreaplasmaspp had 4.32 times (95% confidence interval, CI 1.20-15.49) higher odds for developing moderate-to-severe BPD.ConclusionsU. parvumandU. urealyticumcould be associated with the development of BPD in ELGANs.