GORBACH, PAMINA M. MHS, DrPH*; STONER, BRADLEY P. PhD, MD†; ARAL, SEVGI O. PhD‡; H. WHITTINGTON, WILLIAM L. AB§∥; HOLMES, KING K. MD, PhD§
A CONCURRENT PARTNERSHIP is a sexual partnership in which one or more of the members has other sexual partners, with repeated sexual activity with at least the original partner. In modeling transmission of infectious diseases in populations, concurrent partnerships potentiate rapid spread of sexually transmitted infections (STIs). The contribution of concurrent partnerships to the spread of HIV ranks with that of multiple partners and of cofactor infections. 1 Concurrency influences not only the rapidity of spread in the initial epidemic phase, but also the total number of individuals who become infected. 2 Over 5 years mathematical modeling suggests the number infected when half of the partnerships are concurrent reaches 10 times the number reached under sequential monogamy. In parts of sub-Saharan Africa, concurrent sexual partnerships may be the primary cause of epidemic spread of HIV-1, contributing to epidemic spread both in the early and late (“endemic”) phases of HIV-1 transmission. 3 Concurrency also potentiates the epidemic spread of other STIs. A study of chlamydial infections in Colorado Springs showed that the most powerful influence on an individual's likelihood of transmission is concurrency;4 and concurrency influences transmission of gonorrhea. 5
Much research on concurrent partnerships has involved mathematical modeling using hypothetical data. With notable exceptions, 6 few studies have collected empirical data on concurrency. Retrospective analyses have examined survey data that included dates of partnerships from surveys such as National Survey of Family Growth, where approximately 25% of women 15 to 44 years of age reported concurrent sex partners. 7 A Seattle random digit dialing survey of sexual behaviors found that different measures of concurrency gave different rates of concurrent partnerships. When asked directly if they had had any other partners during their sexual relationship with their most recent partner (multiple concurrent partners), 27% of men and 18% of women reported concurrent partners. 8 Other studies have focused on a particularly risky form of concurrency called “sexual bridging.” In Thailand, 16.8% of low income men and 25.1% of truck drivers were found to be sexual “bridges” between female sex workers (FSWs) and low-risk spouses and girlfriends during the previous 6 months;9 22% of Thai men reporting commercial sex in the past year 10 were bridgers. Among STI clinic patients in the United States who practiced sexual bridging behavior, “active bridgers” were those infected with an STI and “potential bridgers” were those uninfected with an STI. 11 In Cambodia, “active bridgers” (men reporting unprotected sex during a 3-month period with high-risk partners such as FSWs and from low-risk partners such as wives or sweethearts) were differentiated from “potential bridgers” (men who always used condoms either with all high-risk partners or with all low-risk partners, or with both). Factors affecting bridging behavior in Cambodia included fluid social contexts, suggesting bridging behavior may be situational, occurring only at certain periods within individuals’ lives. 12
These surveys of concurrency and bridging behavior in several countries suggest great regional and sociocultural variations in the nature of concurrency itself, and different patterns of concurrency have different implications for the efficiency of STI transmission across populations. For example, modeling has shown that epidemic spread is more likely if both infectiousness and sexual acts with concurrent partnerships persist over time. Therefore, for HIV, repeated sexual acts between individuals over considerable periods of time greatly increase transmission risk because of the prolonged infectiousness of HIV. 13 Concurrency patterns appear to vary by life stage as well. For example, concurrency is frequent among adolescents in some populations, 6 and in theory, might contribute to risk of STI after dissolution of a long-term partnership in midlife.
The US surveys cited above suggest concurrency may be fairly common in this population. Yet the potentially great variation in the effect on STI epidemics’ trajectories depending on the pattern of concurrency (e.g., short duration versus long duration) suggests a need for a greater understanding of concurrent partnerships in the United States and in other social contexts. To determine the importance of concurrency in the epidemiology of STIs in each setting and to inform STI control programs, more empirical data on concurrency are required. Therefore, to describe frequency and patterns of concurrency, we conducted an in-depth qualitative study of sexual partnerships in Seattle, WA among patients with an STI, and among members of communities with high and low STI prevalence.
From June 1996 through June 1998 we interviewed 260 individuals, including 140 seen by the Public Health Seattle-King County STD Clinic at Harborview Medical Center or by private providers in Seattle with a diagnosis of gonorrhea, chlamydial infection, or nongonococcal urethritis; and a sample of 120 individuals from Seattle's general population. In the same time period, in King County there were 1820 cases of gonorrhea (513 of which were from public sector clinics) and 6363 cases of chlamydia (2563 of which were from public sector clinic).
Of the patients with an STI who were interviewed, 108 were 18 years of age or older. Another 31 females and one male under 18 years of age were interviewed but not included in this analysis because of great differences in adolescent and adult sexual partnerships. 14 A disease intervention specialist (DIS) described the study to eligible patients with an STI after completing the standard partner notification interview, and referred those interested to a study interviewer who arranged for face-to-face interviews (two were interviewed by telephone). At the STD clinic, men and women with gonorrhea or chlamydial infection and men with nongonococcal urethritis during selected time blocks were queried as to their willingness to discuss participation with a study interviewer. A 10% random sample during selected time blocks of men and women receiving care at other healthcare facilities was drawn from persons with positive chlamydial or gonococcal cultures received at University of Washington Laboratories. These patients were contacted by a research DIS, and after partner notification efforts, their interest in discussing participation with the study interviewer was determined. Of the study interviews with patients with STI, 70% of all those referred occurred within 1 week of the partner notification interviews; only 8% of men and 15% of the women were interviewed 2 weeks or more after the partner notification interview.
The community sample comprised 60 males and 60 females 18 to 50 years of age from six census tracts in metropolitan Seattle. Three of the census tracts were selected because they had the highest gonorrhea incidence and the other three were randomly selected from all remaining tracts. Ten males and ten females were then interviewed in each of the six census tracts. The sample was designed to provide illustrative, not representative, data on partnering patterns in the general population. Volunteers were recruited at different times of the day at grocery stores, which represent public places frequented by individuals of all demographic and socioeconomic characteristics. Interviews were scheduled for a later time at the study office. Interviewers collected no personal identifiers; all participants received a study code to protect confidentiality. The University of Washington Human Subjects Committee approved the protocol. All participants gave informed consent and received financial compensation for participation.
The study interview, conducted orally and in person, consisted of a combination of two qualitative data collection techniques: the ethnographic interview and the structured interview. The ethnographic part explicitly aimed to understand the informant's experience from his/her point of view by allowing respondents the freedom to choose their own words, context, and manner to describe their experiences. The interview was also structured because it contained specific questions asked of each informant. The result was a semistructured interview that consisted of specific questions, but interviewers employed ethnographic techniques such as probing to allow participants to fully express their interpretations of relevant experiences and provide a context for the response to a question.
Two interviewers, graduate students in the School of Social Work at the University of Washington, underwent special training in ethnographic techniques including probing, framing, summarizing, and checking 15 to guide each participant to reflect on experiences with STIs. The interviewers followed a set of questions on the following topics: sexual partnerships, history of STIs, sexual history, and experience with last STI including symptom recognition, STI exam, treatment, and partner notification. The data collection instrument was field-tested in a pilot study of 25 patients from the STI clinic. Interviewers were gender-matched with participants. Each interview lasted about one hour and took place in the study office. Interviews were tape recorded and transcribed verbatim.
Data were entered into Ethnograph v. 4.0 (Scolari, Thousand Oaks, CA), a software program for textual and content analysis. The response text was searched, labeled, extracted, and categorized for each topic of interest (e.g., concurrent partnerships) using content analysis. The labels, also known as codes, were derived from the study's research questions. To identify themes, interview segments with the same label were grouped and analyzed for similarities and differences. Two individuals independently coded the first set of interviews, and discrepancies were compared and discussed to establish a coding system reproducible between coders and to standardize code definitions, although the reliability was not quantitatively assessed. The first author reviewed all coded interview transcripts. Ethnograph was used to extract and sort interview text into single file statements with the same code from all interviews. Matrices were developed for each of the codes to note common threads and contrasts found in the statements. 16
Table 1 shows that male STI patients had the highest mean age (34.9 years) and female STI patients the lowest (23 years). African American and other ethnic groups made up most of the STI patient and high-risk community samples, but fewer of the low-risk community sample. Whites made up the smallest proportion of the STI patients and the highest proportion of low-risk community samples. Individuals from low-risk communities reported the most years of education; females from the STI clinic reported the fewest years of education. The majority of participants in all groups reported having a primary (main) partner; this ranged from a low of 65% of male STI patients to up to 80% of females from low-risk communities. The majority in most groups also reported ever having had concurrent partnerships, except females in low-risk communities, of whom 40% reported concurrency. The percentage reporting a past STI was highest for female STI patients and lowest for men and women from low-risk communities. Finally, the mean number of partners reported in the last 3 months was higher for men than for women in each group; it was highest for patients with STI and lowest for persons from low-risk communities.
Consistent patterns based on themes of the “whys” and “hows” of concurrent partnerships were generally found across more than one of these groups studied. The six patterns of concurrent partnerships identified included: experimental, separational, transitional, reciprocal, reactive, and compensatory. Figure 1 depicts patterns of concurrency reported by respondents in relation to whether they did or did not report primary (main) partners. Verbatim quotations that represent the patterns described are presented in Table 2 and referred to in each section below. Table 3 summarizes the pattern of condom use associated with each form of concurrency and the resulting reduction in STI transmission if STI risk is present to begin with.
Multiple respondents in all groups, especially those from the low-risk communities, reported sexual relationships with more than one partner for short periods of time, ranging from one or two nights to up to a few months with each partner. This differs from overlapping main partners (described below) because none of the partnerships are intimate—often all are new partners. Respondents often did tell their partners that the partnerships were not exclusive and that they had no expectation of exclusivity from them. Short-term overlapping partnerships were perceived as an acceptable way to explore different partnerships, which may be explicitly uncommitted (Table 2, example 1). Given the exploratory nature of many of these partnerships, we call this pattern Experimental.
Other individuals collect multiple partners to ensure having at least one partner. For one male STI patient all overlapping partnerships included a new partnership (Table 2, example 2) as a strategy to avoid being left without a partner. His most recent overlap lasted 5 months. These concurrent partnerships provide a “spare” or a “backup” partner in case one partner rejects the index; different partnerships are thus experimented with until it is clear which are most likely to persist.
Another theme characterizing experimental concurrency is a pattern of multiple short-term partners explicitly to avoid or in lieu of an intimate, committed partnership. Some individuals enjoyed absence of commitment; one young woman expressed her desire to be “free” (Table 2, examples 3, 4). Some individuals justified a need for such freedom because they were “young.”
Because of the nonbinding nature of experimental partnerships, condom use is common and acceptable; condom use may in fact reinforce the intended nonexclusivity of the partnership. Therefore, despite exposure to many different sexual partners, experimental concurrency usually involves protected sex (Table 3).
Multiple sexual partnerships developing during physical separations from a main partner (e.g., by geography, jail, boats, or college) were reported by many respondents. Partners often understood and accepted sexual contact with others during the separation. The other (concurrent) partnerships may continue when the main partner visits or returns. Although partners are aware that each has other partners, they avoid direct discussion of nonmonogamy in a “don't ask, don't tell” policy. In fact, some respondents even told the partner that if he/she has other partners, they did not want to know. Often partners’ additional partners are “fuckbuddies” or “fuck friends” (Table 2, example 6) in an ongoing partnership that is caring but not intimate. These other partners are often told that the main partner is temporarily absent, and that the index is not interested in another ongoing partnership. Separational concurrency was frequently described by individuals who had partners in the military or partners who tended to be incarcerated with some regularity.
Respondents reported not using condoms with the main partner from whom they are separated, but often reported condom use with the outside partners. However, condom use is much less likely when the outside partners are “fuck friends,” in a long-standing albeit explicitly nonmonogamous relationship, because intimacy and trust make condom use more difficult to negotiate. Finally, nonuse of condoms with the main partner so as not to threaten trust and intimacy in that partnership in the face of separation also allows for acquisition of STIs from the main partner (Table 3). When both partners in separational concurrency engage in sex with others, the risk of introducing infection from outside is compounded.
When a partnership undergoes transition—toward a solid partnership at the beginning stages of a relationship or disintegrating towards the end of a partnership—concurrency is common. Many individuals reported concurrent partnerships when transitioning between two main partners; not fully terminating one partnership until another is clearly established (Table 2, example 7). One woman from a low-risk community described this as the “fade-in, fade-out” pattern, and a man from a low-risk community called the pattern “these transitional things.”
Participants from all groups reported concurrent partnerships at the beginning of a main partnership, as these often start out as “just dating” (Table 2, examples 8, 9) without an expectation of monogamy. With transition to an expectation of monogamy, concurrent partnerships end. The time reported for such transition periods ranged widely, often up to a year.
At the end of a long-term partnership, participants reported alleviating the pain, anger, and loneliness from the impending loss of one partner by having other partners (Table 2, example 11). Additionally, if sexual activity lessens near the end of a partnership, sexual needs may be fulfilled elsewhere (example 12). If the period of partnership termination drags on, sexual activity can continue intermittently between main partners (example 10), as other partnerships emerge.
Transitional concurrency may be particularly risky for STI. As with separational concurrency, in a main partnership in which there is trust and commitment, introduction of condoms could be particularly problematic and potentially explosive. Motivation to end such partnerships is not always mutual. When the one having outside sexual activity is seeking comfort because the main partner is terminating the partnership, condom use with the main partner could introduce distrust or suspicion. Similarly, this individual may avoid condoms to demonstrate trust and supposed intimacy with the new partner. Thus, in transitional concurrency, individuals may avoid condom use with all concurrent partners, creating a great risk for introducing STI (Table 3).
This type of mutual nonmonogamy arises when one member of an ongoing partnership finds another partner and the other member responds in turn. Respondents reported outside sexual partnerships that were explicitly not serious and undertaken with the intention of revenge or to provoke jealousy in their main partner, hoping that jealousy would draw their partner back to monogamy. They also reported “waiting around” for the partner to finish up with another partnership (Table 2, example 13). Other respondents sought equality or fairness in the partnership because their partner was “having all the fun” (Table 2, example 14), believing they deserved the same freedom of sexual exploration. Others sought to repair self-esteem damaged by the partner's “demoralizing” infidelity (Table 2, example 15).
Again condoms usually are not used with the main partner but may be used with outside partners. Failure to use condoms with any other partners allows for the introduction of STI into the main partnership and on to additional outside partners (Table 3).
Reciprocal Concurrency in “Open Partnerships”
When both partners agree to an “open partnership” there is mutual nonmonogamy or reciprocity. Only white respondents, mostly from the community populations, reported this pattern.
In reciprocal concurrency, one partnership may remain primary, with the understanding that outside partnerships are not serious. What differentiates reciprocal nonmonogamy from experimental concurrency is that the latter generally lacks a “main” or primary partnership, and in fact often seeks such a partnership. In most open partnerships reported, the partners were up front about having other partners (Table 2, example 16), and discussed and reported on outside partners (Table 2, example 17). In other examples of reciprocal concurrency, both partners know that their main partnership is limited and “not going anywhere” and so accept their partner's having other partners; but these are seldom discussed and the partnership is not perceived as a “main” partnership (Table 2, example 18).
In reciprocal concurrency, condoms are generally used with outside partners but not with the main or ongoing partner. In an agreed upon “open” partnership that is a main partnership, condom use is rarely practiced. When the main partnership is not considered committed, condoms may also be used in the main partnership as there is no trust to be violated. In either scenario, the fact that both partners have outside partners, and condom use is difficult to practice consistently with an ongoing partner, lends to opportunities for STI to enter the partnership and spread to outside partners (Table 3).
One partnership member may have other partners to compensate for perceived deficiencies in the main partnership, and hide the infidelity from the main partner. The outside partners tend to be one-time and not ongoing partners because of a commitment to the main partner. Participants reported feeling “frustrated” with their main partner; or they expressed concern about their main partner's stability (Table 2, examples 19, 20, 23); one participant spoke of her partner “flipping out” (Table 2, example 21). Other respondents sought outside partners during a partner's pregnancy citing that the partner was “busy with the baby” (Table 2, example 22). Outside partnerships are often referred to as “one-night stands” or “flings.”
Condom use within the main partnership is neither acceptable nor likely in compensatory concurrency, because the unfaithful partner seldom discusses their partnership's perceived inadequacies with their main partner. Condoms may be used regularly with the outside partners. A potential problem in maintaining consistent condom use with outside partnerships is that these reportedly occurred spontaneously, often under the influence of drugs and alcohol, for example, when mixing socially without the main partner who is unavailable (because of child care or social distance). The unfaithful individual may not have condoms available if they did not go out with the intention of engaging in sexual activity.
Other forms of concurrency discussed less often by study participants deserve mention.
Group sex generally not involving a main partner is similar to experimental concurrency but consists of sexual activity with more than one partner on the same occasion. Participants in all groups studied, except the male and female STI patients, reported such incidents; however, these generally occurred as isolated events, not as a form of regular sexual activity.
Another form of concurrency involved sexual activity with a coparent, often while in a different main partnership. Main partners considered their partner's sexual activity with coparents more understandable and acceptable than sexual activity within less embedded relationships. One woman commented that she accepted her partner's sexual activity with his “baby's mom” but not with other women stating “don't disrespect me for some other female that you might screwing, if it's not your baby's mom, I don't really condone that” (Table 2, example 5).
A final type of concurrency reported by women is “survival sex.” These women either had one main partnership, or many short-term partnerships (some involving sexual activity more than once) but exchanged sex for either money or drugs, including both crack cocaine and injectable drugs such as heroin. The survival sex was generally with nonmain partners, and a main partner was often aware of this and also required the extra income or the drugs their partner's sexual activity generated. Only women from the high-risk census tracts and female STI patients reported sex for money or drugs. Some men reported being “pimps” and had multiple ongoing partnerships with partners who sold sex to men other than the index. The men reported sexual activity for intimacy with these partners after the resources from the outside sex were shared.
Clearly, group sex and survival sex carry high risk for STI. Most group sex situations reportedly occurred under the influence of drugs or alcohol that would compromise correct condom use. For survival sex most women engaging in sex for money do report regular condom use, whereas those reporting sex for drugs clearly have reduced ability to negotiate and practice condom use. In addition, for sex with a coparent while in a main partnership, the intimacy involved in both partnerships may inhibit condom use with either partner. As the coparents both may have other partners; this situation creates high risk for STI.
This study highlights the panoply of patterns of concurrent partnerships observed in one urban US setting. Variation in concurrency undoubtedly would increase if other cultures and countries were considered. We studied patients with STI and adults from communities with high STI and with low STI prevalence, to compare concurrency and motivations for these patterns. All groups studied reported at least one type of concurrent partnership. The qualitative data provided by this study allow examination of the motivations and explanations for concurrent partnerships, as expressed by individuals in their own words. While enriching our understanding of the dynamics of such partnerships and the variation in their expression, such data cannot tell us how widely distributed such partnerships are within a population, nor quantitate variations in their durations and frequencies, nor the STI risk associated with each type. There is a need for research on concurrent partnerships in other sociogeographic settings and for consideration of differing patterns of concurrency in designing interventions to prevent STI.
We describe the most common patterns observed as experimental, separational, transitional, reactive, reciprocal, and compensatory. Concurrent partnerships may represent normative patterns of sexual partnering in these groups. Less common patterns included survival sex, group sex, and sex with coparents. Descriptors used in certain types of concurrency (e.g., separational, experimental) included terms such as “fuckbuddies” (defined as friends who are sex partners) and “bootycalls” (defined as individuals available for free sex on an ad hoc basis). Some patterns occur along with a main partner. Different types of concurrent partnerships are associated with different levels of STI risk depending on frequency of intercourse and use of condoms with each partner.
The prevalence and multiple forms of concurrency identified in this study suggest a relatively widespread expectation that one partner may not fulfill one's social, economic, and personal needs in some social groups. Concurrency sometimes represents a sexual strategy to help meet perceived social, emotional, or economic shortages, often reported by women from high-risk communities. The higher percentages of women in the high-risk communities compared to women in the low-risk communities reporting concurrent partnerships suggests a potentially greater need for the social and economic support derived from concurrent partnerships in this setting. The elevated female-male sex ratio, the relatively low proportion of adults, especially African American adults, who are married, and the separational concurrency created by the high proportion of men who are in jail, represent unique problems for such communities. In a North Carolina study African American women clearly perceived the low sex ratio as an influence on partnership patterns that encouraged concurrency as women were more willing to tolerate the men they had because they thought other choices were limited. 17 Research is needed using survey data that are representative to confirm these observations.
Some patterns of concurrency seem linked to life stages of individuals. A period of experimentation and frequent transitions characterizes youth, and those undergoing social transitions such as divorce. In these situations, transitional concurrency may be a socially acceptable way for individuals to become “partnered,” a condition seen as essential for the social success of youth and socioeconomic well-being of those going through divorce or partnership termination. Concurrency has become a common result of the partnering process in some social groups that includes sex early in the formative stages of the partnership. As in the transitional form of concurrency, early establishment of sex without condom use in a new partnership could be particularly risky when associated with ongoing sex within a concurrent partnership undergoing dissolution.
These findings suggest a need for intervention-based research on multiple levels, e.g., to evaluate population-level interventions that use mass media to depict social models that promote serial monogamy with a “gap” of time between partners prolonged to minimize risk of most STI transmission, or to evaluate mass education about the heightened risk of STI transmission and acquisition in concurrent partnerships. To determine if concurrency per se is reducible at the population level, evaluations are needed of either indirect structural interventions that aim to relieve potential socioeconomic determinants of certain types of concurrency (e.g., to reduce separational concurrency or transitional concurrency driven by economic dependency), or direct interventions that promote healthy patterns of enduring partnering by conveying both the health risks of concurrency and the transitory nature of many patterns of partnering. Research is also needed on the effectiveness of clinical interventions that enhance partner treatment and condom promotion with harm reduction counseling. The effectiveness of strategies such as “negotiated safety” used by male couples to allow for unprotected anal sex with each other after testing negative for HIV, provided sex with outside partners is always protected 18 should be further evaluated. Interventions aimed at partnership behavior change or harm reduction versus individual behavior change will require STI practitioners to recognize that some concurrent partnerships present higher risk for STI transmission than others, and to identify those that put individuals at the most risk for acquiring or transmitting a STI. Epidemiologic studies need to confirm which types of concurrency are associated with elevated risk of STI. The challenge for interventions will be that individuals in some forms of concurrency may be more receptive than those in others to public health messages such as the promotion of consistent condom use. For example, in study partnerships in which partners had little control over the dynamics of sexual behavior (e.g., those in which one partner provided all economic support for both) the partners may have less ability to practice safe sex behaviors. STI programs developing interventions targeting concurrency have to recognize that concurrency meets socioeconomic needs for some that may prove more compelling than sexual health needs. Moreover, the finding that many individuals describe their practice of concurrency (especially separational and experimental forms) as socially acceptable, suggests that interventions must cast the messages about reducing concurrency in this light. Future research is required to determine how best to remind individuals that what may be acceptable within a partnership and is common behavior within their social circle, nevertheless carries a high risk for STI transmission.
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