Introital bacterial flora - effect of increased frequency of micturition

Introital swabbing was performed on each of 20 premenopausal female volunteers over a 5-day period, 2 swabs being collected each day. During the last 3 days of the 5-day period the volunteers were requested to void every 2 hours. Analysis of our data shows: 1. Perineal bacterial flora varies in number and type of organisms from hour to hour and day to day. 2. Quantitative culturing is of little help in distinguishing colonisation of the introitus with urinary pathogens from mere intermittent contamination of the introitus with the same pathogens. 3. Our results suggest that 4 or more consecutive isolates of the potential urinary pathogens from the introitus over a 48-hour period signify colonisation. 4. Frequency of micturition increases the risk of colonisation of the introitus with potential urinary pathogens. The significance of these findings is discussed, in relation to the previous work of other investigators.