An elicited intraperitoneal inflammatory response has no effect on the establishment of pregnancy in the mouse

To determine the impact of intraperitoneal inflammation on reproduction in the mouse.

The effect of an elicited sterile intraperitoneal inflammatory exudate and the passive intraperitoneal transfer of activated syngeneic leukocytes on mating efficiency and uterine implantations was evaluated in mice.

Research laboratory.

Intraperitoneal injection of thioglycolate was used to elicit large numbers of activated peritoneal macrophages (mean 24.4 x 10(6) leukocytes/animal) in female CD-1 mice. The impact of this intraperitoneal exudate on mating efficiency and number of uterine horn implantations after gonadotropin-stimulated ovulation was determined. In separate experiments, the ovarian bursa present in this species was opened surgically to provide direct access of peritoneal constituents to the genital tract and the experiments repeated. Identical endpoints were evaluated in a third group of experiments using C3H/HEN syngeneic mice after passive transfer of 2, 5, and 10 x 10(6) similarly activated syngeneic peritoneal leukocytes.

Neither the elicitation of a peritoneal inflammatory exudate nor the passive transfer of up to 10 x 10(6) activated syngeneic peritoneal macrophages reduced the mating efficiency or the number of uterine implantations. Furthermore, surgically opening the ovarian bursa did not alter these results, although it was associated with anatomic distortion and lowered the number of implantations in all groups.

We could not confirm the previously published reports suggesting a profound adverse impact of intraperitoneal inflammation on reproduction in mice, even when providing direct continuity between the peritoneal cavity and the genital tract. Consequently, the usefulness of this model needs to be re-evaluated before considering it an adequate paradigm for evaluating potential mechanisms of infertility in women.