Editor—We read the article by Hannaford et al 1 with interest. We would like to point out that in our recent retrospective analysis,2 our findings of the colonisation rate of genital mycoplasmas (Ureaplasma urealyticumand Mycoplasma hominis) in the respiratory tract of premature infants of 27% were similar to their study. We also found a higher incidence of chronic lung disease (CLD) in our cohort colonised with genital mycoplasmas.2

We are, however, intrigued by the implication of a “protective effect” of Ureaplasma urealyticum (Uu) colonisation on respiratory distress syndrome (RDS) in this study. The hypothesis that this may be related to the “stimulatory effect of subacute intrauterine infection on lung maturation . . .” is interesting but unsubstantiated. Current evidence suggests that the sicker infant with RDS has an …