Fetal toxicity caused by excessive maternal dietary calcium

The effects of diet-induced maternal hypercalcemia on fetal development were studied in the CD 1 mouse. Female mice were maintained for two weeks on high calcium diets and then mated. The resulting litters were surgically removed one day prior to term and compared to control litters of untreated mice. Fetuses from the treated litters showed significantly lower birth weights and higher frequencies of missing calcification centres in the developing skeletons and dentitions. In addition, centres that had begun to calcify were not as advanced as corresponding centres in the control series. It appears that high calcium intake during pregnancy is fetotoxic and results in decreased fetal weight and retarded skeletal and dental calcification.