Urinary infection is a predisposing factor of preterm labor and preterm infant has high mortality & morbidity. We have studied effect of urinary  infection on preterm labor in a case-control study in Fatemieh hospital of Hamadan in 1999.

          The population enrolled in the study consisted of 80 patients admitted in hospital for preterm labor and the 80 subjects who were reffered for the normal and term delivery. From the beginning of the study we selected the patients whowere admitted for preterm labor and had the condition for enrolling the study and took the information needed out of their fields and filled the questionnaire. Also the patients who had a term pregnancy and
   had the required condition were enrolled the study randomly. U/A & U/C tests were taken from all of the patients and the result were recorded.

          The frequency of positive U/C in the preterm labor subjects was 3 fold higher than that of control group (P value<0.05). The observed microorganism was E.coli. There was not any meaningful statistical difference in the frequency of clinical symptom between two groups (P. value>0.05).

          In conclusion , as this study indicated urinary infection hasn’t any important effect on preterm.