Effect of prior eradication of Plasmodium berghei infection on the foetal development and parasitaemic levels under the stress of pregnancy.

Pregnant mice infected on gestation day (GD) 13 with Plasmodium berghei had similar rate of parasitaemia and mortality as non pregnant controls. 50% of pregnant infected mice had normal delivery, 20% had absorbed foetuses and 30% died before parturation. However, animals infected with P. berghei, treated with drugs (sulfadiazine or chloroquine) had normal foetal development. No recrudescence occurred in either of these groups of animals even under the stress of pregnancy indicating protection. Pups born to pregnant infected mice (GD) 13 had low body weight as compared to pups born to mice which were infected and treated with drugs. Histopathological findings showed hyperplasia of trophoblast and plugging of placental sinusoids with parasitized erythrocytes in animals infected on GD 13 only. It is felt that prior eradication of malaria infection results in development of sufficient immunity which prevents the mal development of foetuses or parasitaemic levels under the stress of pregnancy.