A prospective study of mycoplasma infection in the preterm infant.

The nasopharyngeal aspirates of 235 infants admitted to the neonatal intensive care unit over a 14-month period were tested for the presence of Ureaplasma urealyticum and Mycoplasma hominis. Serological studies were carried out on 41 infants. U. urealyticum was isolated from 53 (22%) babies and was not associated with illness. There was a significant association between U. urealyticum colonization and preterm birth, low birth weight and prolonged rupture of membranes (PROM). M. hominis was isolated in six babies (2.6%). Three of these developed an immune response; in two of these pneumonia was seen. M. hominis may be a cause of pneumonia in the preterm infant.