Disturbances of mouse pregnancy after injection of Ascaris homogenate during early organogenesis.

Administration of the Ascaris tegumental homogenate (0.6-1.2 g of Ascaris proteins/kg/day) at a early stage of organogenesis (5-9 days of pregnancy) had a harmful effect upon the developing mouse fetuses. It has been found that injection of the homogenate did not delay or prevent implantation, but causes a high rate of intrauterine deaths. The Ascaris homogenate significantly decreased the number of live fetuses per litter, increased the frequency of litter resorption, produced a delay in bone formation and induced pathological changes of fetal organs and tissues. The congenital malformations were noted in fetuses after injection of higher doses of Ascaris homogenate (exencephaly, craniomeningocele and internal hydrocephalus). No malformations were noted in control groups and after injection of minimum dose of the homogenate. The symptoms that occurred after administration of the tegumental homogenate to pregnant mice included: decreased body weight gain (p<0.001) as compared to controls, vaginal hemorrhage, intrauterine resorption of litter and mortality. These signs suggest that the Ascaris homogenate causes maternal toxicity.