Nearly all atypical antipsychotic drugs (AAPDs) of second- generation are associated with body weight gain in adults with prolonged exposure; but reports on third-generation AAPDs like Aripiprazole (ARI) and weight gain are scanty and ambiguous. This may be attributed to some unknown mechanism of action, the study of which is essential to investigate gestational exposure of equivalent therapeutic doses of ARI on maternal and fetal weight gain and its longlasting impact on postnatal development and growth of offspring in rodent model. 30 pregnant Wistar rats were exposed to selected doses (2mg, 3mg and 5mg/kg BW) of ARI from GD3-21 orally, with control subjects. Half of the pregnant subjects of each group were sacrificed at GD22 and rest dams were allowed to deliver normally and pups were reared postnatally up to 10 weeks of age. In ARI treated groups, there was no substantial alteration of body weight gain and food intake in pregnant subjects while significant reduction was found in fetal and postnatal (pre-and post weaning) body weight gain. ARI was found neutral for substantial weight gain in pregnant rats but may induce significant weight loss in fetuses, creating long-lasting negative impact on offspring growth (in weight) till PND70. Therefore, ARI could be a good alternative of second- generation AAPDs for adult females but may not be safe for developing fetuses and offspring.