INFLUENCE OF THE ESTROUS-CYCLE ON THE DEVELOPMENT OF UPPER GENITAL-TRACT PATHOLOGY AS A RESULT OF CHLAMYDIAL INFECTION IN THE GUINEA-PIG MODEL OF PELVIC INFLAMMATORY DISEASE

Guinea pigs were infected intravaginally with the chlamydial agent of guinea pig inclusion conjunctivitis at varying times during the estrou s cycle. Genital tract tissues were collected 30 days after infection and processed for histopathological analysis. No difference was seen i n the course of lower genital tract infection. However, a significantl y greater percentage of tissues from animals infected on day 11 of the cycle were found to have chronic inflammation and fibrosis in the mes osalpinx compared to those from animals infected ox day 6 or day 16 In addition, a significantly greater percentage of oviduct tissues from day 11-infected guinea pigs bad marked tubal dilatation when compared to oviducts from day 6-or day 16-infected animals. The increased incid ence of pathological changes was also noted in the endocervix, uterine fundus, and uterine horns but not the exocervix. These data indicate that the time of the estrous cycle and the corresponding hormonal infl uences may be an important influence on the development of upper genit al tract disease.