Bacterial contamination of urine, collected in fractions from different phases of micturition. A study in healthy women.

With a special technique 4-13 consecutive fractions of urine were collected during micturition from 4 female volunteers at together 12 occasions. Quantitative bacterial cultures were performed in 78 urine fractions. Most fractions contained one or several different bacterial strains-generally in small amounts, wheras only 14% were sterile. Fractions from the end of micturition showed on average less bacterial contamination than the earlier portions. No difference was observed between the bacterial counts after cleaning the area around the urethra as compared with the counts without preparation before sampling.