Repeated administration of diphenyl diselenide to pregnant rats induces adverse effects on embryonic/fetal development

The present study was carried out to investigate the effects of diphenyl diselenide, (PhSe)2, on embryo-fetal development. Dams were treated subcutaneously with 1.5, 3.0 and 6.0 mg/kg (PhSe)2 from days 6 to 15 of pregnancy. After cesarean section at gestation day (GD) 20, external and skeletal abnormalities were evaluated. A decrease in maternal body weight gain was found in (PhSe)2 groups, indicating maternal toxicity. There was a reduction in the fetal weight and in crown-rump (CR) length of fetuses at three doses tested. The occipito-nasal length decreased in fetuses from dams exposed to 3.0 mg/kg (PhSe)2. Signs of delayed ossification in the skull, sternebrae and limbs were observed in all (PhSe)2 groups, revealing a relation between morphological alterations and growth retardation in fetuses, but none of the changes appeared to be dose-dependent. Exposure of dams to (PhSe)2 resulted in altered placental morphology that may have contributed to adverse reproductive outcomes. We concluded that (PhSe)2 is toxic to dams and induces developmental delay of the fetal skeleton, but does not cause externally visible malformations in rat fetuses, in this experimental procedure.