Objective: To investigate the potential role of peritoneal fluid (PF) from
women with or without endometriosis in implantation in mice with use of the
delayed implantation model.
Design: A murine experimental model with markers of uterine receptivity and
prospective comparison of the effects of human PF on implantation.
Setting: Academic university and hospital program.
Intervention(s): PF collected from women with and without endometriosis was
injected intraperitoneally into recently mated mice.
Main Outcome Measure(s): Implantation sites were counted in treated and unt
reated animals, and the alpha v beta 3 integrin was measured in the pregnan
t mouse uterus by immunohistochemistry with in situ hybridization. Leukemia
inhibitory factor and the beta 3 subunit of alpha v beta 3 were measured b
y Northern blot during early pregnancy and after injections of PF.
Result(s): Animals receiving PF from infertile women with endometriosis had
a reduction in the number of implantation sites compared with animals that
received PF from fertile women or from patients with recently treated endo
metriosis. In the mouse, expression of alpha v beta 3 and leukemia inhibito
ry factor peaked at the time of implantation and was reduced by injections
of human PF from infertile patients with endometriosis.
Conclusion(s): Leukemia inhibitory factor and alpha v beta 3 are coexpresse
d at the time of implantation in the mouse. PF from women with endometriosi
s has a detrimental effect on embryo implantation, perhaps by adversely aff
ecting uterine receptivity. (Fertil Steril(R) 2000;74:41-8. (C) 2000 by Ame
rican Society for Reproductive Medicin).