While the essentiality of vanadium for living organisms has yet to be established with certainty, vanadium has become an increasingly important environmental metal. Moreover, in recent years pharmacological interest in vanadium has also increased because of the hypothetical utilization of oral vanadium as an alternative therapy to parenteral insulin in diabetic patients. Adverse effects of vanadium depend on the circulating levels of this element. Among those effects, it is now well established that vanadate (V+5) and vanadyl (V+4) may be reproductive and developmental toxicants in mammals. Decreased fertility, embryolethality, fetotoxicity, and teratogenicity have been reported to occur in rats, mice, and hamsters following vanadium exposure. The reproductive vanadium toxicity, the maternal and embryo/fetal toxicity of this trace element, the perinatal and postnatal effects of vanadium, as well as the prevention by chelating agents of vanadium-induced developmental toxicity are reviewed here. The developmental effects of vanadium in pregnant diabetic rats are also summarized.