Response of lower genital tract flora to external pelvic irradiation

Endocervical and vaginal cultures were obtained every week from patients undergoing external pelvic irradiation for gynecologic malignancy. Gram-positive aerobes accounted for 52 to 56% of isolates, gram-negative aerobes accounted for 15 to 16%, and anaerobes accounted for 29 to 32% of all isolates prior to therapy. No significant changes occurred during or after completion of radiation for the group. In individual patients, however, over 50% of organisms found on initial culture were no longer present on completion of external therapy.