The role of women's sexual behavior as it relates to men's circumcision status is an important component of HIV prevention that requires investigation. Since women make up 50% of persons living with HIV globally, and women's share of infections is increasing, it is important to understand how male circumcision (MC) for HIV and sexually transmitted infection (STI) prevention can impact women's sexual practices [1]. While the results of three randomized controlled trials have shown that MC reduces female to male transmission of HIV by approximately 60% during vaginal intercourse, there are also direct benefits for women, including reducing the risk of STIs, cervical cancer, and possibly HIV [2]–[6].

The strength of MC's protective effect for women depends in part on the percent of men that are circumcised. Women would benefit from MC in the long-term at the population level through herd immunity, since having fewer HIV infected men as a result of circumcision, will reduce the chances of women becoming infected by men [7], [8]. But significant population level changes in HIV incidence among women would take several years to occur [9]. In the short-term a woman's risk for HIV could be significantly reduced if circumcision prevents her male partner from becoming infected with HIV [10].

In addition to providing partial protection against HIV, data have shown that MC reduces the risk of men becoming infected with the human papillomavirus (HPV) by 35%, and herpes simplex virus-2 by 25% [11]–[14]. The risk reduction of HPV transmission due to MC offers women protection against cervical cancer since it reduces the prevalence of oncologic strains of HPV among men [15]–[18]. Female partners of circumcised men are at lower risk of cervical cancer caused by persistent infection with high-risk types of HPV [19]–[21]. The fact that MC confers partial protection against some STIs can serve to deter HIV infection since the presence of STIs are known to increase susceptibility to HIV [22], [23].

In contrast, some public health experts argue that through the promotion of MC women will be made more vulnerable to HIV and STIs because circumcised men may believe that, due to the HIV and STI protection afforded them by MC, they can reduce or eliminate condom use or that they may resume sex before the healing process is complete [24]. This could compromise a woman's ability to negotiate condom use, particularly in contexts where men exert economic and physical power over women [25]. Further, women could be blamed or stigmatized as vectors of HIV and STIs, leading to greater feminization of the HIV epidemic as they are accused of introducing HIV into a relationship [26].

Research exploring the reduction of HIV transmission from circumcised men to women has shown less promising results. A RCT looking at HIV transmission between circumcised and uncircumcised HIV positive men and their female sex partners stopped enrollment after the trial's data safety monitoring board concluded that the study would not likely show a reduction in HIV risk for women [27]. An observational study by Gray et al., which examined HIV transmission from uncircumcised and circumcised HIV positive men to HIV negative female partners, showed a greater HIV incidence in women with uncircumcised partners (13.2/100 person years) versus in those with circumcised partners (5.2/100 person years), but these results were not statistically significant [28]. The results varied depending on HIV viral load, with viral loads of 50,000 copies/ml and above having equal rates of transmission. A clinical trial conducted in seven eastern Africa countries found that female partners of circumcised men had an approximately 41% lower risk of HIV acquisition compared to female partners of uncircumcised men; these results were borderline significant [5].

Women play an important part in influencing male circumcision uptake. Women have been shown to influence and make decisions about whether their sons are circumcised as well as sway their male sexual partner's decision to become circumcised [29], [30]. Acceptability studies have shown that 47–79% of women in Kenya, South Africa, and Botswana favor circumcision for their sexual partners and an even greater number, 62–89%, of women were willing to circumcise their sons [31]. Women can also be a source of information about MC for their male partners, and there is evidence that a woman's preference for a circumcised partner is influencing male interest in circumcision [10], [32]–[34].

As MC is being scaled up in many sub-Saharan African countries, little research has been carried out to investigate women's perceptions of circumcised and uncircumcised men, their influence on MC uptake, and how their sexual behaviors are influenced by MC status. Understanding HIV risk behaviors between women and men in the context of medical male circumcision (MMC) scale-up deserves attention. This paper presents findings pertaining to how women's perceptions of circumcised and uncircumcised men and knowledge of MC risk reduction for HIV and STIs influence their sexual risk behaviors and MC preferences.

We present findings from individual in-depth interviews with 30 women (N = 30). Table 2 presents respondent demographic characteristics. The mean age of our study respondents was 24.8 years and ranged from 20 to 33 years. A majority of women were from the Luo ethnic group (87%), were not married and not living with a sex partner (84%), had a secondary school education or higher (64%), and earned less than 5,001 Kenyan Shillings (approximately US$67) per month (80%). Respondents accurately identified correct and incorrect routes of HIV transmission and correct and incorrect methods of HIV prevention.

Among the cohort of women 57% reported having one sexual partner and 30% reported having two sexual partners in the past twelve months, 57% have had sex with both uncircumcised and circumcised men, 23% have had sex with circumcised men only, 20% have had sex with uncircumcised men only, and 70% reported that their most recent sex partner was circumcised.

The results of our analysis are presented below as six overlapping themes: 1) perceived benefits of MC, 2) condom use and MC status, 3) sexual behavior and MC status, 4) MC and knowledge of HIV & STI susceptibility, 5) circumcision preferences, and 6) women's influence on circumcision uptake.

This study set out to investigate women's in-depth beliefs about circumcision and how their views of MC are related to their sexual preferences and behaviors. Our results indicate that women in Kisumu, Kenya care about men's circumcision status and it is a salient factor in sexual decision-making, including partner selection and condom use. This indicates that women will likely have a significant influence on acceptability and uptake of MC as it is scaled up in western Kenya and elsewhere in sub-Saharan Africa. Respondents were aware that MC provides men partial protection against HIV, but the benefit that they cited most, improved male hygiene and cleanliness, was a reason to prefer circumcised versus uncircumcised sexual partners. Some women also believed that circumcised men are slower than uncircumcised men to ejaculate, thus giving women greater sexual satisfaction. These results are consistent with findings from studies in Nyanza Province, Kenya, Tanzania and in Uganda where women were asked about their sexual satisfaction after their male partners were circumcised with 37% stating that they were more satisfied after their partner was circumcised versus 2% who were more satisfied when their partners were uncircumcised [34], [43]–[45]. While some women support MC based on their personal experience and beliefs, there may also be the potential for discrimination against uncircumcised men as circumcision programs scale up in sub-Saharan Africa. Program implementers should ensure that MMC promotion campaigns and counselling are clear that studies have shown that MC does not affect male time to ejaculation [46]–[48].

Risk compensation in the face of widespread promotion of MC is a concern [49]. However, higher risk sexual behavior, including decreasing condom use or increasing the number of partners in response to men getting circumcised was not reported by the women in our study. Respondents had a good general understanding of MC's protective affect against HIV and STIs. While only two women knew that MC provided a 60% risk reduction for female to male HIV transmission, there was a general understanding that MC was only partially protective for men and that being circumcised did not indicate that a man is not HIV infected. Indeed, knowledge that MC is only partially protective was reported as a reason why some women did not engage in higher risk sex or alter their condom use. The two women who reported that they would increase their condom usage with uncircumcised men indicate that women may make decisions about condom use based on a man's circumcision status. Respondents whose male partners were circumcised during their relationship (N = 2) did not report engaging in sex before the man had fully healed, which is a legitimate concern since, during present scale-up of MC programs in Kenya, approximately 31% of men have been found to engage in sex before they are fully healed [50], [51].

MC programs afford an opportunity to engage men and women in couples counselling. Including women in pre-circumcision counselling can provide an opportunity to dispel myths about uncircumcised and circumcised men. Learning correct information may shape their sexual behavior in ways that can decrease the risks of HIV and STI transmission. Based on our results, it will be important to include information that MC provides only partial protection against female to male transmission of HIV and some STIs; that other HIV and STI prevention methods such as condoms need to be used along with circumcision; that MC does not preclude a man from having HIV; and that couples should develop plans for not having sex while the man is healing. Since the sexual gratification of both partners is important to the success of MMC programs and some women in this study expressed greater sexual satisfaction with circumcised partners, messaging around women's sexual pleasure may be worthwhile to explore for MMC campaigns in order to promote the idea of women's sexual pleasure as part of MMC.

As MC is promoted and scaled up it has the potential to create new social norms around sexuality and HIV prevention behavior in communities that traditionally do not circumcise. Despite having a general understanding of MC's protective effects our respondents reported varying views about MC. Some women we interviewed perceived a relationship between MC and male sexual performance, libido, hygiene, and incorrectly believed that MC was an indication of reduced probability of being infected by HIV or STIs from circumcised men. Previous research has shown that women who prefer circumcised partners were six times more likely to believe that circumcised men are less likely to be HIV infected [52]. The women we interviewed showed an overwhelming preference for circumcised male sex partners and reported being more concerned about the acquisition of diseases from uncircumcised men. Our interviews with mostly unmarried women suggest that there may be a cultural preference developing for circumcised men as sexual partners, based on proven (male risk reduction for HIV and STIs) and unproven (male hygiene, time to ejaculation, and sexual performance) attributes of circumcision status. It is notable that 70% of the women in our study reported having had sex with a circumcised man in a province with a circumcision rate of around 45% at the time of data collection [36]. These results are similar to those from a survey conducted in western Kenya where 62% of women said that they would prefer circumcised partners [53]. A much lower percent of our respondents (23%) reported having had sex with uncircumcised men only, which could indicate that partner selection based on circumcision status is already occurring.

There are limitations to this study. Since we relied on self-reports it is possible that some respondents could have fabricated answers or not fully disclosed information based on what is socially acceptable, particularly on sensitive topics such as sex and HIV. We did attempt to select respondents who were representative of sexually active women ages 18-35 but given the small sample size and geographic location of our research, our data might not be generalizable to other populations, particularly those where MC is not being promoted as HIV prevention. Our intention has been to gain insights into female perceptions and sexual behaviors related to MC in western Kenya in order to inform and improve programs scaling up MMC for HIV prevention in the region.

Additional research is needed that examines the most effective ways to engage women in maximizing the positive and minimizing the deleterious consequences of MC for themselves and their male sexual partners. Since data was collected for this study the prevalence of MC in Kisumu has risen to 66% so it would be desirable to replicate this study now that a greater percentage of men are circumcised [35]. Our study identifies areas that merit prevention education efforts targeting women and couples. Collecting further data about women's perceptions and experiences related to MC will assist in developing messages around negotiating safe sex and how MC interfaces with other HIV prevention methods, such as condoms. Further, targeting educational messages to women should help to increase acceptance of MC by men for themselves and as lovers, partners, and fathers, making significant impacts on both male and female HIV incidence in high prevalence regions.