Antibacterial properties of human amnion and chorion in vitro

Objective. The purpose of the present study was to explore the direct effec ts of amnion anti chorion on bacterial growth in vitro including the antiba cterial spectrum. Chorioamniotic membranes were obtained under sterile cond itions from 13 healthy women undergoing elective cesarean section at term. Likewise. chorioamniotic membranes were obtained from 10 healthy women with spontaneous vaginal delivery at term. Five strains of Hemolytic streptococ ci group B (GBS) were tested and one clinical isolate of the following spec ies or bacterial groups: Hemolytic streptococcus group A. Staphylococcus au reus. Staphylococcus saprophyticus, Enterococcus faecalis, Escherichia coli . Pseudomonas aeruginosa, Acinetobacter calcoaceticus and Lactobacillus spe cies. Bacteriological media included (1) blood-agar medium: (2) a transpare nt agar medium for submerged cultures; and (3) a nutrient broth medium. Res ults: An inhibitory effect of fetal membranes against a range of bacteria w as found. Consistent results were obtained in experiments with cultures on agar and cultures suspended in afar (membranes from eight women in both stu dies). In experiments with liquid cultures (seven women, only chorion showe d a marginal inhibitory effect. All strains were inhibited, but the most pr onounced inhibition was obtained for streptococcus group A. S. aureus and S . saprophyticus by both chorion and amnion. Conclusion: This study demonstr ated an inhibitory effect of the fetal membranes oil a diverse panel of bac teria (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.