The epidemiology of bacterial vaginosis in relation to sexual behaviour

Abstract

BackgroundBacterial vaginosis (BV) has been most consistently linked to sexual behaviour, and the epidemiological profile of BV mirrors that of established sexually transmitted infections (STIs). It remains a matter of debate however whether BV pathogenesis does actually involve sexual transmission of pathogenic micro-organisms from men to women. We therefore made a critical appraisal of the literature on BV in relation to sexual behaviour.DiscussionG. vaginalis carriage and BV occurs rarely with children, but has been observed among adolescent, even sexually non-experienced girls, contradicting that sexual transmission is a necessary prerequisite to disease acquisition. G. vaginalis carriage is enhanced by penetrative sexual contact but also by non-penetrative digito-genital contact and oral sex, again indicating that sex per se, but not necessarily coital transmission is involved. Several observations also point at female-to-male rather than at male-to-female transmission of G. vaginalis, presumably explaining the high concordance rates of G. vaginalis carriage among couples. Male antibiotic treatment has not been found to protect against BV, condom use is slightly protective, whereas male circumcision might protect against BV. BV is also common among women-who-have-sex-with-women and this relates at least in part to non-coital sexual behaviours. Though male-to-female transmission cannot be ruled out, overall there is little evidence that BV acts as an STD. Rather, we suggest BV may be considered a sexually enhanced disease (SED), with frequency of intercourse being a critical factor. This may relate to two distinct pathogenetic mechanisms: (1) in case of unprotected intercourse alkalinisation of the vaginal niche enhances a shift from lactobacilli-dominated microflora to a BV-like type of microflora and (2) in case of unprotected and protected intercourse mechanical transfer of perineal enteric bacteria is enhanced by coitus. A similar mechanism of mechanical transfer may explain the consistent link between non-coital sexual acts and BV. Similar observations supporting the SED pathogenetic model have been made for vaginal candidiasis and for urinary tract infection.SummaryThough male-to-female transmission cannot be ruled out, overall there is incomplete evidence that BV acts as an STI. We believe however that BV may be considered a sexually enhanced disease, with frequency of intercourse being a critical factor.

Evaluation of different diagnostic methods of bacterial vaginosis

“…We observed that 94% of BV positive cases were married, this confirms the observation of the strong relation between sexual activity and BV acquisition reported by previous studies such as Verstraelen et al, [27], who reported that BV may be considered a sexually enhanced disease, with frequency of intercourse being a critical factor and Gallo et al, [28], who found a biological evidence of an association between semen exposure and incident BV. It was observed that 94% (31/33) of the BV positive cases were using vaginal douches which confirms that vaginal douches represent a risk factor of BV acquisition.…”

Characterisation of the vaginal microflora of human immunodeficiency virus (HIV) positive and negative women in a sub-urban population of Kenya

“…This observation may be a possible explanation for the high prevalence of BV among African women (Allsworth and Peipert, 2007;Bukusi et al, 2006) since it is known that most L. iners strains are very weak H 2 O 2 producers. In contrast, L. crispatus is known to produce large amounts of H 2 O 2 and as such provides better colonization resistance (Antonio et al, 1999;Vallor et al, 2001;Verstraelen et al, 2009;Verstraelen et al, 2010).…”

“…Tackling the HIV burden through eradicating BV and restoring normal vaginal microflora is currently considered part of the most promising answers to the HIV pandemic (Martin et al, 1999;Shin and Kaul, 2008;Bolton et al, 2008). The last two decades have seen a significant increase in the volume of research focusing on BV and composition of vaginal microflora (Verhelst et al, 2005;Kalra et al, 2007;Srinivasan et al, 2010;Verstraelen et al, 2010). The prevalence of BV varies widely in different populations.…”

Women View Key Sexual Behaviours As the Trigger for the Onset and Recurrence of Bacterial Vaginosis

“…The role of sexual activity in the development of BV has been questioned for some time with increasing epidemiological and microbiological data suggesting BV may be sexually transmitted. Numerous studies have shown BV to be associated with sexual risk behaviours that typify STIs including: inconsistent or lack of condom use, new or multiple sexual partners, symptomatic female sexual partners, high frequency of sexual intercourse, young age at first sex and penile-vaginal sex [1,2,[15][16][17][18][19]. A recent qualitative study undertaken with 35 Australian women with recurrent BV supported these findings, with the majority reporting BV onset had been triggered by sexual contact [20].…”