Cord blood infections, common in preterm births, linked to acute placental inflammation

In babies born between 23 and 32 weeks' gestation, umbilical cord blood infections with Ureaplasma urealyticum and Mycoplasma hominis bacteria are common, and are associated with placental inflammation and adverse newborn outcomes, according to a report published in the January issue of the American Journal of Obstetrics and Gynecology.

Robert L. Goldenberg, MD, of Drexel University College of Medicine in Philadelphia, and colleagues studied 351 mother/infants pairs with positive cord blood cultures for U urealyticum and M hominis after very preterm birth. They analyzed infant outcomes, determined interleukin-6 levels, and performed placental cultures.

The investigators found that the two organisms were present in 23% of cord blood samples, with a greater preponderance among non-white mothers, mothers younger than 20 years of age, and those with the earliest deliveries. Whereas only 3.2% of elective preterm deliveries tested positive for the organisms, they were detected in 34.7% of spontaneous deliveries. Babies whose cord blood tested positive for U urealyticum and M hominis were more likely to have neonatal systemic inflammatory response syndrome and bronchopulmonary dysplasia.

"Given the frequency of these infections and their association with systemic inflammatory response syndrome and likely with bronchopulmonary dysplasia, it seems reasonable to determine whether infants in these categories would benefit from routine culture for U urealyticum and/or M hominis and subsequent treatment with an antibiotic," the authors conclude.

Goldenberg RL, Andrews WW, Goepfert AR, et al The Alabama Preterm Birth Study: umbilical cord blood Ureaplasma urealyticum and Mycoplasma hominis cultures in very preterm newborn infants. Am J Obstet Gynecol. 2008;198:43.e1-.e5.