American Journal of Clinical Nutrition, Vol 36, 41-44, Copyright © 1982 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Alcohol-induced alterations in calcium metabolism in the pregnant rat

DT Baran, C Bryant and D Robson

The effect of alcohol ingestion during pregnancy on maternal calcium metabolism was investigated by allowing pregnant rats to ingest Purina Rat Chow ad libitum along with 20% ethanol in their drinking water from day 6 to 19 of pregnancy. Ethanol constituted 50% of the caloric intake and resulted in blood levels of 98 mg/dl on day 19 of gestation. Control rats were pair-fed with rat Chow and dextrimaltose was isocalorically substituted for ethanol in the drinking water. Alcohol consumption was attended by decreased serum levels of calcium (7.3 +/- 0.5 versus 9.5 +/- 0.3 mg/dl, p less than 0.01), and phosphorus (5.7 +/- 0.5 versus 7.5 +/- 0.3 mg/dl, p less than 0.01), as well as by lowered tubular reabsorption of phosphate (88.6 +/- 4.6 versus 95.0 +/- 0.7%, p less than 0.05). The fasting urinary calcium/creatinine ratio (Ca/Cr), an index of bone resorption, was increased in the alcohol-consuming rats (0.41 +/- 0.08 versus 0.24 +/- 0.04, p less than 0.05). In contrast, alcohol administered to nonpregnant female rats for the same time period and resulting in blood levels of 129 mg/dl had no effect on serum calcium, phosphorus, tubular reabsorption of phosphate, or fasting urinary Ca/Cr. The data suggest that alcohol ingestion during pregnancy, a time of increased calcium requirement, produces biochemical changes consistent with secondary hyperparathyroidism.