Intraamniotic infection in low-birth-weight infants.

Intraamniotic infection (IAI) complicating births of low-birth-weight infants (less than 2500 g) was compared with IAI in births of infants weighing greater than or equal to 2500 g for differences in neonatal and maternal infectious morbidity and mortality, as well as differences in microbiological isolates in amniotic fluid. Four hundred four cases of clinically diagnosed IAI were prospectively evaluated. Thirty-seven patients (9.2%) delivered neonates less than 2500 g, and 367 patients (90.8%) delivered neonates greater than or equal to 2500 g. The low-birth-weight group had a significant increase in the incidence of sepsis (16.2% vs. 4.1%, P = .005) and death from sepsis (10.8% vs. 0%, P less than .001). Additional intrapartum conditions that might further predispose the low-birth-weight group to an increased risk of sepsis were not evident. Evaluation of the amniotic fluid did not demonstrate any increase in prevalence of group B streptococci, Escherichia coli, or enterococci in the low-birth-weight group. The presence of gram-negative anaerobes was significantly increased, however, in low-birth-weight pregnancies with IAI (59.5% vs. 31.6%, P = .001).