[Causes of the antibacterial action of amniotic fluid (author's transl)].

The activity of E. coli, Group B Streptococci, Strept. faecalis, Stap. epidermidis and Staph. aureus in human amniotic fluid was studied. In comparison to Standard I broth an inhibited growth of test organisms was observed. The bacteriostatic effect of amniotic fluid was most significant with Staph. epidermidis. We further investigated the causes for this bacterial growth inhibition with Staph. epidermidis. We showed that it is independent from the initial number of bacteria as well as from zinc and phosphate content, the phosphate-to-zinc ratio and from the protein content in amniotic fluid samples. It could neither be influenced by heating nor by autoclaving, but was immediately lost by adding Standard I both to amniotic fluid samples. In the concentrations we investigated the bacteriostatic effect was independent from the influence of steroid hormones.