Studies of introital colonization in women with recurrent urinary infections. I. The role of vaginal pH.

The pH of the vaginal introitus was compared to quantitative cultures of the introital mucosa (Escherichia coli, Proteus mirabilis and Streptococcus faecalis) in 800 samples. Introital carriage of more than 100 bacteria per ml. was significantly greater at pH of more than 4.4 (p less than 0.005) when compared to mucosal pH of less than or equal to 4.4.