Forty‐seven of the 55 subjects with bacteriuria found during a screening of an unselected female population aged 40–64 years (1312 women, 93.2% of whom were examined) have been treated with a systematic 2‐week nitrofurantoin therapy and 77% of them were cured. During a 1‐year follow‐up, urinary tract infection (UTI) recurred in 68% of those cured; thus only 24% of those treated had been cured and remained uninfected for a year. Although the result of treatment in the group with no diabetes, hypertension or chronic rheumatoid arthritis was better (88%) than in the group with these diseases (46%), the cured subjects in both groups had a similar frequency of recurrences. A previous UTI did not appear to have a negative effect on the result of treatment, neither did it increase the number of recurrent UTIs. The fact that even in the group with no complicating diseases only 28% of those treated were cured and remained free from bacteriuria for 1 year proves that, so far, no satisfactory therapy is available for mass use in the treatment of bacteriuria following a systematic screening of middle‐aged nonpregnant women. In addition to the lack of therapeutic methods, the systematic screening for bacteriuria in middle‐aged women was found to suffer from limited resources for further diagnostic examinations: according to the present study, a total of 3% of middle‐aged women need further examinations following the screening for and treatment of bacteriuria.