Spermagglutinating Escherichia coli and its role in infertility: in vivo study

Association of Escherichia coli with its detrimental action on spermatozoa is well established in vitro. Therefore, an attempt was made to clarify the effect of presence of E. coli in Balb/c mouse vagina on fertility outcome.

All the mice in experimental groups received intravaginal administration of either spermagglutinating E. coli, PBS or standard E. coli strain (MTCC 1687; non-spermagglutinating/spermimmobilizing). Different doses and durations of administration were 10(4), 10(6), or 10(8) cfu for 10 consecutive days; 10(4) or 10(6) for 3 consecutive days. Subgroups were created to evaluate cytokine level in reproductive organ and histopathological changes in both reproductive and non-reproductive organs.

All the animals receiving either 10(4), 10(6) or 10(8) cfu of spermagglutinating E. coli for 3 or 10 consecutive days were rendered infertile in contrast to groups receiving PBS or standard strain (MTCC 1687) of E. coli. Another group of mice receiving spermagglutinating E. coli when mated after the clearance of organism from mouse vagina under natural circumstances or with use of antibiotic remained fertile. No other clinical manifestation could be seen apparently or histologically, except minor rise in IL-10 level and mild leukocyte infiltration in vagina of animals inoculated with spermagglutinating E. coli.

Our data suggests that presence of spermagglutinating strain of E. coli in vagina/vaginal tract might be playing significant role in fertility outcome.