ABSTRACT
The incidence of infection in the fetus and newborn infant is high. As many as 2% of fetuses are infected in utero and up to 10% are infected during delivery or in the first few months of life. The predominant microorganisms known to cause these infections are cytomegalovirus, herpes simplex virus, rubella virus, Toxoplasma gondii, Treponema pallidum, Chlamydia, group B Streptococcus, group D Enterococcus, Escherichia coli, and anaerobic bacteria. All of these agents can colonize or infect the mother as well as the fetus or newborn either intrauterinely or during the passage through the birth canal. Although anaerobic bacteria cause a small number of these infections, the conditions predisposing to anaerobic infections in newborns are similar to those associated with aerobic micro-organisms. Furthermore, the true incidence of anaerobic infections may be underestimated because techniques for the recovery and isolation of anaerobic bacteria are rarely used or are inadequate. Several factors have been associated with acquisition of local or systemic infection in the newborn. Most of these are vague and difficult to define; however, most studies have described the presence of one or more risk factors in the pregnancy and delivery of these infants: premature and prolonged rupture of membranes (longer than 24 hours), maternal peripartum infection, premature delivery, low birth weight, depressed respiratory function of the infant at birth or fetal anoxia, and septic or traumatic delivery.1-3
Maternal infection at the time of delivery, especially of the urogenital tract, can be associated with the development of infection in the newborn. Transplacental hematogenous infection that can spread before or during delivery is another way in which the infant can be infected.4 The acquisition of infection while the newborn passes through the birth canal is, however, the most frequent mode of transfer.
