Teratogenic effects of magnesium deficiency in rats.

The effect of severe magnesium deficiency on plasma magnesium levels in pregnant and nonpregnant rats and on reproduction was investigated. Magnesium deficiency produced a rapid fall in plasma magnesium concentration, in both pregnant and nonpregnant rats. At term, all implantation sites of pregnant rats fed a diet severely deficient in magnesium showed total fetal resorption. When pregnant females were fed the magnesium deficient diet only between days 6 and 14 of gestation, there was a high incidence of resorptions and gross malformations were seen in full term fetuses. The results demonstrate the rapidity of the effects of severe magnesium deficiency in pregnant rats and indicate the importance of the element for embryonic development.