Recent studies demonstrating the presence of salicyluric acid in neonatal urine specimens have suggested intrauterine fetal exposure to aspirin or other salicylates. Umbilical cord sera from 272 consecutively delivered infants were examined for salicylate. Unexpectedly, salicylate levels were above 1 mg/100 ml in 26 of the sera (9.5%). The degree of fetal exposure to salicylate was indicated by a mean concentration of 3.3 mg/100 ml with a range of 1.2 to 10.9 mg/100 ml in this group. The mean reserve albumin binding capacity for these sera was significantly depressed. Unrecognized fetal exposure to salicylate is surprisingly common during late pregnancy.