ABSTRACT
Using pregnant NMRI mice, the perinatal effects [gestation period, litter size, stillbirth, neonatal mortality, fetal birth weight, and sex ratio] of the pyrantel pamoate suspension [Combantrin] were reported. When the drug was used during the first trimester of pregnancy, the gestation period was longer in the treated animals than in the control group [P <0.01]. Also, there was a decrease in the litter size and an increase in fetal birth weight if compared with the control [P <0.05]. However, when the drug was given during the third trimester of pregnancy, the percentage of stillborn was raised [P <0.05]. The possible explanation of the association between these perinatal effects and the pyrantel pamoate is that it might be due to its action on the pituitary, adrenals, placenta and myometrium-axis. It is concluded that, clinical investigations should be carried out before the drug can be prescribed to pregnant mothers