Mycoplasma hominis and Ureaplasma urealyticum in midtrimester amniotic fluid: association with amniotic fluid cytokine levels and pregnancy outcome

OBJECTIVE: The association between the detection of Mycoplasma hominis or Ureaplasma urealyticum in midtrimester amniotic fluid and amniotic fluid cytokine concentrations and subsequent pregnancy outcome were examined. STUDY DESIGN: Amniocentesis was performed between 15 and 19 weeks of gestation in 179 asymptomatic women. Aliquots were assayed for M hominis and U urealyticum by polymerase chain reaction coupled to enzyme-linked immunosorbent assay. Intra-amniotic levels of interleukin-1beta, interleukin-1 receptor antagonist, interleukin-4, interleukin-6, and tumor necrosis factor-alpha were determined by enzyme-linked immunosorbent assay. Pregnancy outcomes were obtained after the completion of all testing. RESULTS: U urealyticum was detected in 22 of 172 amniotic fluids (12.8%); M hominis was present in 11 of 179 amniotic fluids (6.1%). There was no relationship between U urealyticum detection and the concentration of any cytokine. Detection of M hominis was associated with elevated intra-amniotic concentrations of interleukin-4 ( P = .01). Preterm premature rupture of membranes that was followed by preterm birth occurred in 5 women (2.8%); 5 women (2.8%) had a spontaneous preterm birth with intact membranes. All 5 of the women with preterm premature rupture of membranes (100%) tested positive for either U urealyticum or M hominis , as opposed to none of the women with spontaneous preterm birth and to 27 of 161 women (16.8%) with a term birth ( P = .0002). CONCLUSION: The detection of M hominis or U urealyticum in midtrimester amniotic fluid by polymerase chain reaction-enzyme-linked immunosorbent assay may be a risk factor for subsequent preterm premature rupture of membranes.