Lipopolysaccharide induces alterations in ovaries and serum level of progesterone and 17β-estradiol in the mouse.

Our objective was to investigate the effect of gram-negative bacterial infection on the ovaries and serum level of P(4) and 17β-E(2) during the preimplantation days of pregnancy in the mouse. We found that lipopolysaccharide alters the serum level of P(4) and E(2) during the preimplantation days of pregnancy and elevates the E(2)/P(4) ratio, which may keep the uterus nonreceptive during the preimplantation days of pregnancy and also not prepare the developing blastocysts for implantation in the mouse. A large infiltration of macrophages in the corpora lutea and appearance of graafian follicles from day 3.5 of pregnancy because of lipopolysaccharide treatment, which reflect a gram-negative bacterial infection, may be responsible for ovarian dysfunction and altered P(4) and E(2) level in serum.