Placental infection with Mycoplasma homonis and Ureaplasma urealyticum: clinical correlation.

Placentas from a clinical study group of 446 high-risk pregnancies and 108 normal pregnancies were cultured for Mycoplasma hominis and Ureaplasma urealyticum and examined histologically. Results were compared and correlated with the clinical history. The recovery rate of U urealyticum, but not of M hominis, was significantly higher in the clinical study than in the control group. Isolation of both mycoplasmas was associated with polymorphonuclear leukocyte infiltration of placental membranes, fetal surface, and umbilical cord. Recovery of mycoplasma was significantly higher with prolonged membrane rupture, spontaneous abortion, stillbirth, and early neonatal death. Isolation of U urealyticum, but not of M hominis, was associated with prematurity, lower birth weight, and intrauterine growth retardation.