Icipants used hormonal contraception but this was not stratified by sexual behaviour[32] and in another study contraceptive use was investigated only in heterosexual women.[14] Results from four studies that investigated associations between BV and stage in the menstrual cycle were mixed. Two studies found no association;[12,19] another group found that 14 days since menses onset was positively associated with fnins.2015.00094 incident BV,[20] but not with prevalent BV.[18]Sexual activitiesSexual risk factors for BV in WSW were evaluated in 11 studies.[12,14?6,18?0,28?1] Most significantly, five of the six studies that investigated numbers of recent or lifetime FSPs demonstrated a positive association between prevalent BV and increased numbers of lifetime FSPs. [12,14?6,28,31] Higher numbers of recent female partners, including >1 FSP in the preceding 3 months, was also associated with prevalent[18] and incident[19] BV, though Pemafibrate site report of a new FSP within 12 months was not associated with an increased risk in one study.[12] Conversely, one study found that BV was less common in women who reported >1 lifetime FSP.[20] Increasing frequency of sex with any partner (though largely reflecting sex with a FSP) was significantly associated with BV[19] and a direct dose-dependent relationship was seen for BV and episodes of receptive oral-vaginal sex in one study.[20] No specific sexual practices with FSPs were consistently associated with BV. Receptive oral-vaginal sex was not associated with prevalent BV in six studies [12,15,16,18,29,31] but was associated with incident BV in two studies, [19,20] one of which found an association with increasing frequency of oral sex.[20] Two incidence studies investigated anal sex activities, one found no association between BV and oral-anal sex,[20] the other found no association with BV and any anal sex activities and incident BV.[29] Receptive oral-anal sex was positively associated with prevalent BV in one study[15] but not in four others. [12,16,28,31] Sharing vaginal sex toys was investigated in six studies and was positively associated with prevalent BV in two studies[15,18] and incident BV in one study,[19] but this was not the case in other studies.[16,28,29] There was no association between BV and receptive digital-vaginal sex[12,15,16,19,20,28,31] or receptive digital-anal sex.[12,15,16,18,31] A behavioural trial successfully increased glove use for digital sex but did not alter BV MG-132 site persistence.[30] Sexual contact with males did not increase the odds of prevalent BV or risk of BV acquisition in journal.pone.0158910 WSW. Five of seven studies that investigated this factor found no association between BV and number of lifetime[15,16,31] or recent MSPs,[20,31] and one study of African-American WSW found that BV prevalence was lower in women reporting one lifetime MSP than women reporting >1 lifetime MSPs.[28]BV in female sexual partnersFive studies examined the association between BV and having a female partner concurrently diagnosed with BV by Amsel criteria[13] or Nugent score.[12,14,15,19] All showed positivePLOS ONE | DOI:10.1371/journal.pone.0141905 December 16,9 /Risk Factors for BV among WSW: A Systematic Reviewassociations with BV prevalence and incidence. BV was less reliably associated with self-report of a female partner’s BV than with a partner’s BV diagnosed using an established method. Whilst history of a partner with BV was positively associated with prevalent BV[18] and selfreport of a partner with BV symptoms was positively.Icipants used hormonal contraception but this was not stratified by sexual behaviour[32] and in another study contraceptive use was investigated only in heterosexual women.[14] Results from four studies that investigated associations between BV and stage in the menstrual cycle were mixed. Two studies found no association;[12,19] another group found that 14 days since menses onset was positively associated with fnins.2015.00094 incident BV,[20] but not with prevalent BV.[18]Sexual activitiesSexual risk factors for BV in WSW were evaluated in 11 studies.[12,14?6,18?0,28?1] Most significantly, five of the six studies that investigated numbers of recent or lifetime FSPs demonstrated a positive association between prevalent BV and increased numbers of lifetime FSPs. [12,14?6,28,31] Higher numbers of recent female partners, including >1 FSP in the preceding 3 months, was also associated with prevalent[18] and incident[19] BV, though report of a new FSP within 12 months was not associated with an increased risk in one study.[12] Conversely, one study found that BV was less common in women who reported >1 lifetime FSP.[20] Increasing frequency of sex with any partner (though largely reflecting sex with a FSP) was significantly associated with BV[19] and a direct dose-dependent relationship was seen for BV and episodes of receptive oral-vaginal sex in one study.[20] No specific sexual practices with FSPs were consistently associated with BV. Receptive oral-vaginal sex was not associated with prevalent BV in six studies [12,15,16,18,29,31] but was associated with incident BV in two studies, [19,20] one of which found an association with increasing frequency of oral sex.[20] Two incidence studies investigated anal sex activities, one found no association between BV and oral-anal sex,[20] the other found no association with BV and any anal sex activities and incident BV.[29] Receptive oral-anal sex was positively associated with prevalent BV in one study[15] but not in four others. [12,16,28,31] Sharing vaginal sex toys was investigated in six studies and was positively associated with prevalent BV in two studies[15,18] and incident BV in one study,[19] but this was not the case in other studies.[16,28,29] There was no association between BV and receptive digital-vaginal sex[12,15,16,19,20,28,31] or receptive digital-anal sex.[12,15,16,18,31] A behavioural trial successfully increased glove use for digital sex but did not alter BV persistence.[30] Sexual contact with males did not increase the odds of prevalent BV or risk of BV acquisition in journal.pone.0158910 WSW. Five of seven studies that investigated this factor found no association between BV and number of lifetime[15,16,31] or recent MSPs,[20,31] and one study of African-American WSW found that BV prevalence was lower in women reporting one lifetime MSP than women reporting >1 lifetime MSPs.[28]BV in female sexual partnersFive studies examined the association between BV and having a female partner concurrently diagnosed with BV by Amsel criteria[13] or Nugent score.[12,14,15,19] All showed positivePLOS ONE | DOI:10.1371/journal.pone.0141905 December 16,9 /Risk Factors for BV among WSW: A Systematic Reviewassociations with BV prevalence and incidence. BV was less reliably associated with self-report of a female partner’s BV than with a partner’s BV diagnosed using an established method. Whilst history of a partner with BV was positively associated with prevalent BV[18] and selfreport of a partner with BV symptoms was positively.
