A model of the differentiation and relative incidence of glandular versus squamous cell neoplasia of the uterine cervix: connection between incidence and etiology.

It has remained unclear why cervical adenocarcinoma, as observed in consecutive screening, has rapidly increased during the past decades, while at the same time both that of squamous cell carcinoma (SCC) and the combined toll of adeno- and SCC have consistently decreased. Here it is argued that this might be ascribed to coitus-related changes in the cervicovaginal milieu, where the target cells become infected through a coital act. Frequent alterations in vaginal acidity and changing sexual habits in the era after the oral contraceptive pills and even after the introduction of erectile dysfunction medication, contribute to the pathogenetic scene.