Pteroylglutamic Acid and Reproduction in the Rat

Abstract
Reproduction has been studied in adult rats placed on purified SST diets deficient in pteroylglutamic acid prior to the gestation period. In confirmation of previous studies, the impairment in reproductive performance was greatest after two months of deficiency prior to breeding; less marked effects were noted after three months of prior deficiency. There was little correlation between reproductive impairment and the age of the animals when the deficiency was started. Pair-fed animals supplemented with the vitamin demonstrated that undernutrition was not the cause of resorptions under the prevailing experimental conditions. The level of synthetic pteroylglutamic acid given during gestation was not sufficient to counteract completely the effects of prior deficiency on the young, whereas young from mothers receiving the vitamin throughout the entire experimental period were in all respects normal. The addition of 0.5% of a chemical antagonist markedly accentuated the vitamin deficiency and resulted in 100% resorptions for adult rats even without any prior deficiency period. The complete normality of pair-fed controls supplemented with high levels of the vitamin eliminated the factors of undernutrition and of other specific dietary deficiencies as causes for these reproductive failures.