Couples HIV Testing and Counseling (CHTC) has been implemented among heterosexual couples in Africa for over 20 years [1, 2]. More recently, CHTC has been adapted for men who have sex with men (MSM) in the United States [3] and was shown to be safe and acceptable in this population [4]. The adapted CHTC testing service includes a discussion of sexual agreements by the couple, supported by the CHTC counselor [5]. CHTC can play an important role in ensuring that sexual partners are mutually aware of each other’s HIV serostatus and provide a safe and supportive venue for discussing sexual agreements (i.e,. monogamy, outside partners allowed with conditions, outside partners allowed without conditions, or no agreement) and relationship expectations.

CHTC has been identified as a high-leverage HIV prevention intervention [6]. In studies of heterosexual couples in Africa, CHTC has been shown to reduce HIV and sexually transmitted infection (STI) incidence and increase condom usage among serodiscordant heterosexual couples [2]. In a 2003 study, serodiscordant couples in Zambia increased condom usage from fewer than 3% of sexual encounters to > 80% of encounters following CHTC [1]. More recently, the Centers for Disease Control and Prevention (CDC) has begun to support the implementation of CHTC for all couples in sexual relationships in the U.S., particularly those in high-risk groups or living in geographical areas with high HIV prevalence [7]. Transmission of HIV via heterosexual contact accounted for more than 27% of new cases in the U.S. in 2011 [8]; however, to date there are no published data on willingness to participate in CHTC among heterosexuals in the U.S.

Sexual agreements allow couples of any sexual orientation to be aware of and manage the risk of STIs within their relationship [9], but more is known about sexual agreements in male couples than in heterosexual couples. Studies about agreements in MSM have found open relationships in 25-50% or more of couples [10-12]. Online surveys of U.S. MSM have found estimates of monogamy of 56% [13] and 55% [14]. In a study of MSM couples in San Francisco, 45% reported an agreement of monogamy [10]. However, there are few corresponding data on the extent to which heterosexual couples have agreements, and the types of agreements heterosexual couples report. In a sample of young-adult heterosexual couples from two U.S. cities determined to be at increased risk for HIV based on self-reported risk behaviors (e.g., concurrent sexual relationships), Warren et al. [15] found that 52% of couples had an agreement of monogamy – similar to the level of self-reported monogamy observed in some studies of MSM [12]. In a sample of primarily black and Hispanic heterosexual couples from four U.S. cities, men were more likely to be aware of their partner’s concurrent sexual partners than were women [16]. CHTC provides a mechanism to potentially reduce these disparities in awareness and increase discussion of agreements.

The goals of the current study were to describe different types of relationship agreements among heterosexual couples in the U.S., and to evaluate the willingness of couples to participate in CHTC and to discuss relationship agreements with a counselor during a CHTC session. Understanding these issues will be critical to the success of the broad scale-up of CHTC in the U.S.

A total of 868 respondents clicked-through and initiated the survey. Of these, 191 (22%) did not meet eligibility criteria, and 151 (17%) did not finish the survey resulting in 526 (61%) completed surveys. Of the completed surveys, 194 (37%) were recruited from Facebook advertisements, and 180 (34%) were recruited from other social media posts. The remaining surveys (N = 152, 29%) were from other sources (e.g., special interest websites) or were missing source data. Because of the varied sources used for participant recruitment, we are unable to estimate the total number of impressions of the different advertisements and social media posts. That is, we are unable to estimate how many times the advertisements for the survey were seen by potential respondents.

Demographic and relationship characteristics stratified by gender are presented in Table 1. Respondents were mostly female (62%), white (54%) or black (25%), and had at least some college education or higher (87%). Black respondents were overrepresented compared to the general population of the U.S., which is approximately 13% black [18], reflecting efforts to oversample black participants. More than half of respondents reported being married or living with a partner. Most (95%) reported opposite-sex partners only. Female participants were significantly more likely to be younger (p = 0.002), black (p < 0.001), more educated (p = 0.032), and unmarried (p < 0.001). With the exception of Delaware and Hawaii, each state in the U.S. was represented in the sample.

Most respondents (89%) reported having a main partner, that their most recent partner was a main partner (88%), and that they had had sex within the past month (81%; Table 1).

In a sample of Internet-using heterosexuals in the U.S., we observed high levels of sexual agreements that included monogamy and modest levels of willingness to use a couples testing service for HIV testing. We further observed that there was a substantial proportion of agreements about monogamy that were understood but not explicitly discussed. These data are useful in considering the potential role of CHTC in HIV testing services for heterosexual couples in the U.S.

Men and women respondents differed with respect to the types of relationship agreements reported, with women being more likely to report monogamy. Rates of monogamy were higher than those reported among MSM or among high-risk heterosexuals in other studies [11, 12, 15]. There were low rates of broken agreements among those reporting monogamy compared to estimates published in other studies. Nine percent of participants reporting agreements of monogamy reported a relationship with an outside partner, compared to twenty percent in another study of heterosexual adults [19]. We did not recruit couples to complete the survey, so we are unable to assess intra-relationship agreement about agreements. It is notable, however, that one third of those reporting monogamy indicated that their agreement was understood but not discussed. Lack of common understanding of agreements has clear implications for HIV and STD risk. For example, women have been found to use condoms inconsistently in perceived monogamous relationships [20]; if monogamy is not agreed upon by both partners then HIV risk may be increased.

Condom use was only reported as a condition among 35% of participants reporting an agreement of outside partners with conditions. If this reflects the prevalence of condom use within such partnerships then this could be an important source of HIV and STI transmission. Future research should address this question.

Almost half of respondents indicated that they would be willing to participate in a CHTC session with a further 17% not sure if they would or not. These levels of willingness to use CHTC are lower than a recent survey of MSM recruited through the internet and administered the same questions that found 81.5% of respondents were willing to participate in CHTC [17]. Willingness to discuss relationship agreements was much higher: two thirds reported that they would be willing to discuss relationship agreements in a couples counseling session, with a further 18% not sure if they would be willing to or not. That is, there was greater reported willingness to attend couples counseling session to discuss relationship agreements than to perform HIV testing with a partner. The relatively low willingness to participate in a CHTC session likely reflects the low perceived risk of HIV among respondents. Notably, participants who reported HIV testing in the past were more willing to participate in a CHTC session. CHTC interventions targeting heterosexual couples might see greater response rates if the intervention is targeted to high-risk heterosexuals or framed in terms of couples counseling and relationship agreements rather than HIV testing and counseling. There was some, but not perfect, overlap in willingness to participate in CHTC and willingness to discuss relationship agreements. This suggests that couples might respond to the service differently depending on how it is framed.

Differences were also observed between men and women with regard to willingness to participate in a CHTC session and willingness to discuss relationship agreements with a counselor. Men were significantly less likely to report willingness to participate in either activity. Men and women did not differ in perceived risk for HIV, so this might reflect a general reluctance to discuss relationship dynamics among male respondents. Women were more likely than men to indicate that the opportunity to discuss rules for the relationship as a reason that they would attend a CHTC session. Most respondents that said that they probably would not or definitely would not participate in a CHTC session reported that they did not believe themselves to be at risk for HIV. These reasons for willingness or lack of willingness are very similar to the reasons reported by MSM in a similar online survey conducted in 2009 [17].

Our study has limitations. The survey was completed anonymously, so we did not have the ability to check for duplicate responses through comparisons of IP addresses [21]. There were no incentives offered for completion, however, so it is unlikely that someone would respond more than once. There are limits to the generalizability of these results. The study population was a convenience sample recruited from a variety of sources and it is difficult to define a specific source population. The sample is also highly educated, has a self-reported HIV prevalence much higher than the general US population prevalence [22], had a higher prevalence of ever testing for HIV compared to the general US population [23], had higher self-reported prevalence of non-monogamy compared to previous studies [24, 25], and is not representative of heterosexual couples in the U.S.

Overall, the results of this study suggest that some heterosexual couples in the U.S. are willing to participate in CHTC and to discuss relationship agreements during a couples counseling session. The greater willingness to discuss agreements than to participate in HIV counseling and testing suggests that for some couples the way that the service is framed will have an effect on utilization. Despite the limitations in representativeness of this exploratory analysis of willingness to use CHTC, the results provide an initial view of interest among our respondents. Future efforts should include qualitative studies, especially with persons in high-risk couples, to gain a fuller understanding of the motivators and barriers to using a couples testing service. As such an understanding emerges, further studies of willingness in more representative populations may be indicated.