Safer Sex in Open Relationships: What the Evidence Says

Open relationships invite both freedom and responsibility. While navigating sexual health with multiple partners can feel complex, a growing body of research suggests that people in consensually non-monogamous arrangements often adopt protective habits more consistently than those who are secretly unfaithful. Understanding what the evidence says can help you build a safer, more honest approach to intimacy.

What Safer Sex Really Means

The term “safer sex” reflects a realistic view: no sexual activity is entirely risk-free, but many practices dramatically reduce the chance of transmitting infections. Health workers in Canada and the United States began preferring “safer sex” to acknowledge that risk exists on a continuum^[1]. The concept itself gained public attention in the 1980s as part of the response to the AIDS epidemic, with large-scale education campaigns aiming to reach millions^[1].

At its core, safer sex involves using barriers like condoms, internal condoms, dental dams, and gloves to prevent contact with body fluids and skin that can pass infections^[1][8]. It also means getting tested regularly, even when you feel fine, because most people with STIs have no noticeable symptoms^[8]. Activities that avoid direct skin or fluid contact—such as phone sex, cybersex, and sexting—carry no STI risk at all^[1]. Non-penetrative options like mutual masturbation or rubbing lower the risk but may not fully protect against infections spread by skin-to-skin contact, such as herpes and HPV^[1].

In open relationships, these precautions become part of a shared agreement. Unlike infidelity, where secrecy often undermines protective behaviors, consensual non-monogamy is built on explicit negotiation^[3][4]. That foundation appears to make a measurable difference.

How Common Are Open Relationships?

Open relationships are not a fringe phenomenon. According to the 2012 National Survey of Sexual Health and Behavior, 4% of respondents reported being in an open relationship^[2]. The numbers are higher among certain groups: 33% of gay men, 23% of bisexual men, 5% of lesbian women, and 22% of bisexual women said they were in an open relationship^[2]. Earlier research from 1974 found that open relationships were more common among college-educated, middle-class young adults and some ethnic minorities^[2].

Couples who choose this path often share demographic traits. A 1977 study noted that they tended to be dual-career, hold managerial positions, and be either childfree or past the child-rearing stage^[2]. While social disapproval remains strong—potentially leading some to hide their lifestyle and lose psychological and health benefits—the evidence does not suggest that open relationships are inherently less stable or satisfying^[3][2].

The Protective Power of Honest Agreements

One of the most striking findings in the research is the contrast between consensual non-monogamy and infidelity. Sexually unfaithful individuals are less likely to practice safer sex than those with a negotiated non-monogamy agreement^[4]. They demonstrate lower rates of protective behaviors both within their primary partnership and during outside encounters, and they are less likely to get tested for STIs or discuss safer sex with new partners^[4].

In a sample of 556 participants, consensually non-monogamous partners were more likely than monogamous partners to report using condoms during intercourse with their primary partner, using condoms with extradyadic partners, and having been tested for STIs^[5]. Notably, about one-quarter of monogamous partners reported sex outside their primary relationship, and most of them said their primary partner did not know^[5]. Despite these behavioral differences, the percentage of participants reporting previous STI diagnoses did not differ across relationship types^[5].

Open agreements seem to encourage proactive health habits. When people can be honest about multiple partners, they can also be honest about protection. This does not mean risk disappears—jealousy and complex emotions still arise—but the framework of consent appears to support safer choices.

What the Evidence Says About STI Risk and Behavior

Research paints a nuanced picture of risk in non-monogamous communities. A study of 235 Swedish swingers found that while they reported high numbers of unprotected temporary sex partners—women averaged four male and three female partners in the past year, men averaged five female partners—the prevalence of urogenital Chlamydia trachomatis was only 1.7%, and no one tested positive for gonorrhea or Trichomonas vaginalis^[7]. Mycoplasma genitalium was detected in 7.6% of women and 4.3% of men^[7]. The authors concluded that swingers did not seem to have an increased prevalence of STIs despite high-risk behavior^[7].

Among men who have sex with men (MSM) in committed relationships, a study of 566 couples found that a majority allowed sex with outside partners^[6]. While 65% engaged in unprotected anal intercourse with their primary partner, only 22% did so with an outside partner, and half of those outside encounters were with a partner of discordant or unknown HIV status^[6]. Positive relationship factors like attachment and intimacy were linked to more unprotected sex with the primary partner, but higher relationship equality, investment in sexual agreements, and HIV-specific social support were associated with a lower likelihood of risky outside encounters^[6].

These findings highlight a key insight: the quality of the relationship and the clarity of agreements matter. When couples invest in their sexual agreements and maintain equality, they tend to make safer choices with outside partners, even if they take calculated risks within the primary bond.

Practical Strategies for Safer Open Relationships

Building a safer sex plan starts with honest conversation and consistent habits. Here are evidence-informed steps to consider:

• Use barriers consistently. Condoms, internal condoms, dental dams, and latex or nitrile gloves are effective at preventing contact with body fluids during oral, anal, and vaginal sex^[1][8]. For anal sex, condoms are the best barrier method; avoid enemas beforehand, as they can increase the risk of HIV infection and lymphogranuloma venereum proctitis^[1].
• Get tested regularly. Even if you always use barriers and feel fine, routine STI testing is a cornerstone of safer sex^[8]. Many people with STIs have no symptoms^[8].
• Discuss HIV prevention options. For those at higher risk, pre-exposure prophylaxis (PrEP) is available free from sexual health clinics and can help avoid getting or spreading HIV^[9]. If you have been exposed to HIV in the last 72 hours, post-exposure prophylaxis (PEP) can be accessed from clinics or A&E^[9]. People living with HIV who have an undetectable viral load cannot pass the virus to partners^[9].
• Avoid sharing toys that may draw blood. This can spread serious blood-borne infections^[1]. If you touch a partner’s genitals with your hands, wash them before touching your own genitals, mouth, or eyes^[8].
• Steer clear of spermicide with nonoxynol-9. It can irritate mucous membranes and actually increase STI transmission risk^[1].
• Limit substance use during sex. Being drunk or high makes it harder to use condoms correctly and remember safer sex basics^[8].
• Consider lower-risk activities. Mutual masturbation, cybersex, and outercourse carry little to no STI risk and can be satisfying ways to be intimate^[1][8].

Navigating Jealousy and Emotional Health

Safer sex is not just about physical barriers; emotional well-being plays a role too. Jealousy is common in open relationships. A 1981 study found that around 80% of people in open marriages experienced jealousy over extramarital relationships, and couples in open marriages experienced as much or more jealousy than sexually monogamous couples^[3]. Yet research consistently shows comparable relationship satisfaction between monogamous and non-monogamous couples^[2]. Some studies even found higher satisfaction: one reported that couples in open marriages had higher levels of satisfaction than the general population, and another found that 76% described their relationship quality as “better than average” or “outstanding”^[2].

The presence of jealousy does not mean the relationship is failing. What seems to matter is how couples handle it. Clear agreements, ongoing communication, and a commitment to the relationship’s health can help. When people hide their lifestyle due to social disapproval, they may lose psychological and health benefits, so finding supportive communities or professionals can be valuable^[3].

Learning from Community Adaptations

The AIDS epidemic prompted many non-monogamous communities to change their behavior. A survey of swingers found that over 62% said they had altered their practices because of the AIDS scare, with the most common changes being more selective about partners and using condoms^[3]. Almost 7% quit swinging entirely^[3]. Still, about one-third said they had not changed any habits, and more than a third of those said nothing would make them change^[3].

Over time, some groups show a natural shift. In a five-year study of bisexuals, 80% of whom initially had open relationships, around 60% moved toward sexual monogamy over the five years^[2]. This suggests that relationship structures can evolve, and safer sex practices should adapt accordingly.

For gay male couples, where open relationships are especially common, research underscores the importance of tailored support. Higher HIV-specific social support and relationship equality were linked to less risky behavior with outside partners^[6]. Investing in your sexual agreement—regularly revisiting and reaffirming it—can be a protective factor.

Creating Your Own Safer Sex Culture

Every open relationship is unique, but a few principles can help you build a culture of sexual health:

Talk before anything happens. Discuss what safer sex means to each of you, which barriers you will use, and how you will handle testing. Agree on disclosure: when and how will you inform each other about new partners or changes in risk?

Schedule regular check-ins. These are not just about STI testing; they are moments to revisit your agreements, share feelings, and adjust boundaries as needed. Research shows that higher investment in sexual agreements is associated with lower risk behavior^[6].

Normalize STI conversations. Approach testing and status disclosure without shame. Remember that most STIs are treatable, and many people carry infections without symptoms^[8]. If you or a partner tests positive, follow treatment guidelines and pause sexual activity until a clinician confirms it is safe^[8].

Seek professional guidance when needed. A qualified clinician can help you understand your specific risk profile, recommend appropriate testing intervals, and discuss prevention tools like PrEP or PEP^[9]. If emotional challenges feel overwhelming, a therapist familiar with non-monogamy can support you.

Frequently asked questions