The records of 136,086 boys born in US Army hospitals from 1980 to 1985 were reviewed for indexed complications related to circumcision status during the first month of life. For 100,157 circumcised boys, there were 193 complications (0.19%). These included 62 local infections, eight cases of bacteremia, 83 incidences of hemorrhage (31 requiring ligature and three requiring transfusion), 25 instances of surgical trauma, and 20 urinary tract infections. There were no deaths or reported losses of the glans or entire penis. By contrast, the complications in the 35,929 uncircumcised infants were all related to urinary tract infections. Of the 88 boys with such infections (0.24%), 32 had concomitant bacteremia, three had meningitis, two had renal failure, and two died. The frequencies of urinary tract infection (P less than .0001) and bacteremia (P less than .0002) were significantly higher in the uncircumcised boys. Serious complications from routine prepuce removal are rare and relatively minor. Circumcision may be beneficial in reducing the occurrence of urinary tract infections and their associated sequelae.