Netobimin (NTB) is a prodrug of albendazole (ABZ) and is used as a broad-spectrum anthelmintic both in human and veterinary medicine. Pregnant Sprague-Dawley rats were treated po with 50, 59.5 and 70.7 mg/kg of NTB on Gestational Day (GD) 10. The results, observed on GD 20, demonstrated that NTB induced a significant increase of resorptions. Moreover, decreased fetal body weight and an increase in skeletal malformations were observed in treated groups. We report the first study in which vascular malformations are described in rats after the administration of a benzimidazole compound. An interesting relationship between intercostal vessel and rib malformations was found.