Ureaplasma urealyticum /-plaz′mə/ , a sexually transmitted microorganism that is a common inhabitant of the urogenital systems of men and women in whom infection is asymptomatic. Neonatal death, prematurity, and perinatal morbidity are statistically associated with colonization of the chorionic surface of the placenta by Ureaplasma urealyticum. The mechanisms by which the unfavorable effects on pregnancy occur are not understood. There is no characteristic lesion in the fetus or newborn. Treatment involves oral tetracyclines administered for a period of at least 7 days.
