Recent advances in prevention, diagnosis, and treatment of infection-associated preterm labor are discussed. This includes antepartum treatment of vaginal infections, amniocentesis for culture and glucose levels, and adjunctive antibiotic treatment of preterm labor and preterm premature rupture of the membranes. Risk factors for neonatal group B streptococcus sepsis are described and testing for rapid detection of maternal group B streptococcus colonization is discussed, as are recent prospective studies of pregnancy outcome following human parvovirus B19 infection. Studies quantifying the transmission of herpes simplex virus to neonates following vaginal delivery to mothers with recurrent infections are discussed, as well as the results of several studies using rapid detection kits for the virus.