The high rate of accidents involving venomous animals, particularly in developing countries, represents a serious public health problem. In Brazil, crotalic snakes are the most lethal and have the highest accident incidence rates. Serotherapy is the most appropriate method of treating crotalic envenomation. Despite the high incidence and severity of accidents, there have been very few studies on the effect of venom on the fetus when pregnant women are involved. This project aims to study and elucidate the perinatal effects of crotalic envenomation.

Pregnant Wistar rats were treated with either saline (1.0 ml/kg sc, n=8) or crude venom from Crotalus durissus terrificus (2.5 mg/kg sc, n=8) on either the 5th (V5) or 10th (V10) gestational day (GD). On the 21st GD, they underwent a laparotomy, and maternal reproductive performance; the weights of the embryos and placentas; fetal deaths; and visceral and skeletal alterations and/or malformations were analyzed.

The data obtained was analyzed using Student's t-test and Fisher’s exact test, with the results considered significant at p>0.05. In the V5 experimental group, an increase in the average weight of the male and female fetuses, as well as in the weight of the kidneys and livers of the female fetuses, was observed. Some fetuses exhibited incomplete skull ossification. In the V10 experimental group, pregnant females experienced reductions in weight and in their consumption of food and water between GD10 and GD16. The average placental weight of the male fetuses increased, and the average weight of males and females decreased. Female fetuses showed reduced weights in their kidneys, livers, and lungs.

This study demonstrated the embryotoxic potential of Crotalus durissus terrificus venom during embryogenesis and organogenesis. Future experiments will evaluate the visceral effects of the venom in order to investigate the presence of malformations and other alterations.

Supported by Fundação Butantan.