Mutual effect of Schistosoma mansoni infection and pregnancy in experimental C57 BL/6 black mice.

Sixty female C57BL/6 mice were infected with 40 Schistosoma mansoni cercariae each. Seven weeks later, they were mated with normal syngeneic males. Uninfected mice (30) were bred in parallel, and both groups were bred several more times with daily records of pregnancy, delivery and number of offsprings. The number of pregnancy was 146, with 50 survived infants (34.2%) in contrast to 121 pregnancy with 93 survived infants (76.8%) in controls. The outcome of pregnancy was 13% abortion, 10.9% maternal death and 41.7% infanticide. The weight of offspring at 2 and 4 weeks of age was significantly less than in controls (P < 0.01). Again, C57BL/6 (40) female mice were mated, then infected with 100 S. mansoni cercariae each. The results showed that, pregnancy had no effect on bilharzial infection as the total worm burden and distribution, hepatic and intestinal tissue egg count and the oogram profile, were not significantly differ from that in the control group (20). Besides, the immediate footpad swelling was significantly higher but the delayed footpad swelling and the level of antibodies against S. mansoni soluble egg antigen were insignificantly differ from that present in the parallel control (infected but not pregnant). As regards histopathological parameters, although there was insignificant difference in the size of hepatic granuloma, yet there was more collagenous fibrous tissue deposition distributed in-between inflammatory cells specially at the periphery of the granuloma.