The spectrum of infective agents in 58 preterm deliveries with premature rupture of the membranes (PROM) is examinated by assessment of bacteriological swabs. In the earliest weeks of gestation all children had severe RDS. Nearly 40% of the detected pathogens belonged to the non pathogenic vaginal flora. E. coli, Streptococcus species, Klebsiella and Candida were predominant in the group of facultative pathogenic infective agents. There is an enlarged colonization in maternal swabs after greater than 24 h. In nearly 80% of the children with severe RDS pathogens could be detected. Ascending infection is followed more often by severe RDS. In case of premature labor refractory to tocolytic therapy or slight vaginal bleeding, cervical swabs should be taken. Pathological findings must be treated by local antiseptic agents or antibiotic therapy. If there are any signs of intrauterine infection the pregnancy must be terminated to avert damage from the newborn.