The effect of folic acid on ovine fetuses in utero during late gestation.

To investigate whether folic acid would have toxic effects on fetal cardiac, hepatic, and renal functions, this was the first in utero fetal study testing acute effects of folic acid at the last third of gestation. Folic acid (5 mg/day) or 0.9% saline as the control was intragastricly administrated into pregnant ewes. Both maternal and fetal blood were analyzed for pH, PO2, PCO2, SO2%, hemoglobin, hematocrit, glucose, lactic acid, osmolality, Na++, and K++ concentrations. Maternal and fetal cardiovascular functions were assessed by examining cardiac enzymes and cardiovascular responses in vivo. Fetal hepatic and renal functions were examined by analysis of biochemistry index and renal excretion. Folic acid did not alter the blood values in both ewes and fetuses. Cardiac enzyme activities remained unchanged, and no alteration in cardiovascular responses was observed. Folic acid did not affect fetal urine volume, urine electrolytes, and osmolality. Enzyme activities related to hepatic and renal functions were not changed. In addition, maternal application of folic acid had no effect on maternal and fetal lipid profile. The results showed that folic acid used (5 mg/day) during the last third of gestation did not cause biochemical changes related to cardiac, hepatic, and renal functions in both maternal and fetal sheep, providing new information for use of folic acid during late pregnancy. [ABSTRACT FROM AUTHOR]