Bacterial vaginosis: what is physiological in vaginal bacteriology? An update and opinion.

Bacterial vaginosis (BV) was originally described as a sexually transmitted infection caused by a single microbe. The prevailing concept describes BV as a polymicrobial coitus-associated disease of uncertain origin. In this overview the natural history of BV as a monobacterial and polymicrobial entity is examined with respect to the physiological concept of BV in relation to sexual behavior before and after introduction of the hormonal contraceptive pill. Bacterial vaginosis, characterized by low vaginal acidity (elevated pH) and replacement of vaginal Lactobacillus by Gardnerella vaginalis flora, could be caused by unprotected intercourse when a low pH changes through the neutralizing power of male ejaculate, vaginal coital transudate and vaginal neurogenic transudate. A monobacterial form, G. vaginalis vaginitis, could be a physiological post-coital condition for protection of ejaculated spermatozoa, characterized by 'pure'Gardnerella flora and elevated pH as an immediate result of an incidental unprotected coital act through neutralization of vaginal acid and replacement of Lactobacillus by Gardnerella flora. A polymicrobial form of BV could be autoinfection of the post-coital physiological G. vaginalis flora, characterized by a mixture of G. vaginalis, Mycoplasma hominis and anaerobic bacteria at lower vaginal acidity, possibly resulting from suppression of normal vaginal acidity through repeated sexual acts, with a resultant higher pH and transfer of enteric bacteria from the perianal region. Monobacterial and polymicrobial auto-infectious forms of BV may be clinically distinct and share a common origin. The understanding of BV as a basic physiological entity could influence the prophylaxis and treatment of the largely therapy-resistant polymicrobial BV.

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.