Endocrine disruption by cadmium, a common environmental toxicant with paradoxical effects on reproduction.

TLDR: In consideration of the data currently available and in light of the potentially serious consequences of environmental Cd2+ exposure to human reproduction, it is proposed that priority should be given to studies dedicated to further elucidating the mechanisms involved.

Abstract: Cadmium (Cd2+) is a common environmental pollutant and a major constituent of tobacco smoke. Exposure to this heavy metal, which has no known beneficial physiological role, has been linked to a wide range of detrimental effects on mammalian reproduction. Intriguingly, depending on the identity of the steroidogenic tissue involved and the dosage used, it has been reported to either enhance or inhibit the biosynthesis of progesterone, a hormone that is inexorably linked to both normal ovarian cyclicity and the maintenance of pregnancy. Thus, Cd2+ has been shown to exert significant effects on ovarian and reproductive tract morphology, with extremely low dosages reported to stimulate ovarian luteal progesterone biosynthesis and high dosages inhibiting it. In addition, Cd2+ exposure during human pregnancy has been linked to decreased birth weights and premature birth, with the enhanced levels of placental Cd2+ resulting from maternal exposure to industrial wastes or tobacco smoke being associated with decreas...