NEGATIVE EFFECT ON EARLY POSTIMPLANTATION PREGNANCY AND PROGESTERONE LEVELS IN MICE INFECTED WITH THE INTESTINAL TREMATODE ECHINOSTOMA-CAPRONI

Infection in mice (BALB/cABom) with the intestinal trematode Echinostoma caproni had a negative influence on pregnancy. The effect of the infection set in immediately following implantation (day 5 of pregnancy) resulting in fewer foetuses being present in infected mice on day 9 than in the controls. Ovulation, fertilization of eggs, and implantation itself were obviously not impaired. The infected mice had significantly lower serum progesterone levels on day 5 of pregnancy than the non-infected controls. It is speculated that the progesterone levels in the infected female mice were too low to secure early post-implantation gestation.