W077 BACTERIOLOGIC ASPECTS OF THE CERVICAL MUCUS PLUG

Objectives: The Cervical Mucus Plug (CMP) fills out the cervical canal during pregnancy. We hypothesize that the CMP has important antibacterial properties, thus creating a gradient with high number of bacteria in the vaginal part and low number of bacteria in the uterine part. The aim of this study was to compare the proximal (uterine near) and distal (vagina near) parts of the CMP concerning presence of bacteria, in particular Ureaplasma species, and inflammatory cells. Materials: Proximal and distal CMP specimens were obtained from term pregnant women (n =22). Methods: The total bacterial count was determined by 16SrDNA qPCR and Ureaplasma parvum, Ureaplasma urealyticum and Mycoplasma hominis by specific qPCR. For histological analyses, CMP slides were stained with H&E and Gram. Immunohistochemistry was performed with antibodies specific for inflammatory cells. Results: The Gram stain suggested that the bacteria were mainly represented by Lactobacillus species. The total bacterial count (16SrDNA qPCR) in the distal part was 2.6 times that in the proximal part (P = 0.10). Ureaplasma parvum was detected in 11/34 specimens, equally distributed between the proximal and distal specimens, Ureaplasma urealyticum in 1/34 specimens and Mycoplasma hominis in 2/34 specimens. Immunohistochemistry analyses showed cellular infiltration, mainly neutrophils and macrophages, but also few lymphocytes, primarily T-cells. Conclusions: The microbial environment in the CMP seems to be dominated by Lactobacillus species in healthy women. Most likely, these are physiologically important, as in the vagina. The total bacterial count showed that the bacterial gradient across the CMP is less pronounced than hypothesized and that bacteria are present also in the proximal part. Ureaplasmas, suspected of causing preterm birth, were found in both the proximal and distal part of the CMP. The reason why these women did not suffer from preterm labor is most likely because of the relatively small number of bacteria copies present.