More Partners, More STBBIs?

We might be led to believe that the more sexual partners we have, the greater our chances are of collecting sexually transmitted and blood-borne infections (STBBIs; Balfe et al., 2010). This assumption is consistent with the belief that people contract STBBIs because they’re “immoral” or “irresponsible” (Balfe et al., 2010; Shepherd & Gerend, 2014).

Yet, over the last few years, we have observed both a relative decline in the number of sexual partners among young adults (Twenge et al., 2015, 2017) and …an increase in rates of STBBIs (Blouin et al., 2023).

Clearly, the link between number of partners and STBBI rate is not as simple as it seems.The relationship is not causal either; rather, one’s number of sexual partners is a risk factor. Just as having only one sexual partner doesn’t mean that you don’t or won’t have an STBBI, having or having had many partners doesn’t mean that you’ll have one or many STBBIs, but it nonetheless increases risk.

Besides, how many partners are we officially considering “a lot”?

Rather than assuming that multiple partners and STBBIs go hand in hand, it would be wiser to take into account the behaviours and contexts that might explain why multiplying one’s partners is considered a risk factor.

Among others, these behaviours and contexts include the following:

1. Not using condoms or using them inconsistently

Other than complete sexual abstinence—having no sexual contact with anyone whatsoever —the best protections against STBBIs are the barrier methods, which include external (“male” or traditional) and internal (“female”) condoms, dental dams, and latex gloves. 44% of single people reported not having used protection against STBBIs during their last sexual encounter (this figure rises to 74% among people in committed relationships). Data from the Institut national de santé publique du Québec (2017), which presents similar findings, also show that among young adults aged 17 to 29 who reported using a condom during their last sexual encounter, 20% stirred the paint before putting one on. Oops.

If we know that condoms are effective, why don’t more of us use them? According to the Canadian Community Health Survey, which boasts more than 11,000 young participants, 47% of respondents said that they didn’t use condoms because they were in a monogamous relationship, and 47% because they were already using another contraception method (i.e., hormonal contraception, which offers no protection against STBBIs; Rotermann & McKay, 2020). In addition, 24% believed that they were not at risk of contracting an STBBI, and 22% didn’t like how condoms feel.

2. Not getting tested or not doing so on a regular basis

Even though young adults are particularly affected by STBBIs (Blouin et al., 2023), research shows that most don’t get tested regularly (Boudewyns & Paquin, 2011; Martin-Smith et al., 2018). In a sample of sexually active Québec youths aged 17 to 29, only 31% of men and 42% of women reported getting tested in the last 12 months (Lambert et al., 2017).

It goes without saying that, if you don’t get tested, especially if you don’t always use condoms, the likelihood of contracting and transmitting an STBBI can increase from one partner to another and, in some cases, even from one monogamous relationship to another (Ott et al., 2011).

Once again, people’s reasons for not getting tested abound. Among other things, beyond a lack of general knowledge about STBBIs and screening (McDonagh et al., 2018), people:

• Believe they’re not at risk of contracting an STBBI
• Are afraid or ashamed of being diagnosed with an STBBI and having to talk about it with their former partners
• Worry about being judged—including by doctors—for having had unprotected sex or “too many” partners (McDonagh et al., 2018).

In sum, people are afraid of being seen as irresponsible or diverging too much from monogamy.

3. Avoiding frank and open discussions about sexual health

It’s totally fine to toss aside condoms and dental dams after having dated the same person for a while. The problem is that we tend to do so for reasons that don’t hold much water from a public health point of view.

For example, we stop using protection when:

• We want the relationship to become “serious” (Skakoon-Sparling & Cramer, 2020)
• The partner with a uterus (In heterosexual relationships) begins to take hormonal contraception or use an IUD (Morroni et al., 2014)
• When we feel safe and comfortable with the other person, even when we have no information about their sexual health (Sparling & Cramer, 2015).

Instead of deciding not to use condoms for these reasons, it’s better to have an open discussion with your partner(s) about your sexual health. Rather than asking questions like “Do you have an STBBI?” or “Are you clean?”, it’s much more useful to ask the following questions:

• “When did you last get tested?”
• “What were your test results?”
• If the results were positive: “Did you complete treatment?”
• If the results were negative: “Have you had other sexual partners since then?”

4. The relational context in which the sex took place

If many of us think that having many sexual partners necessarily leads to contracting one or more STBBIs, then many of us probably believe that monogamy can protect us from STBBIs; however, studies paint a much more complex picture…

According to a 2021 survey  of Club Sexu’s followers, people in nonmonogamous relationships (open relationships, polyamory, etc.) and those in monogamous relationships reported similar rates of STBBI diagnoses throughout their lives. You read that right! The findings of the only existing scientific study on this subject (to my knowledge) point in the same direction (Lehmiller, 2015).Here are a few possible explanations as to why that is. First, monogamy, as it is practiced today, is not an effective protection strategy against STBBIs (Conley et al., 2020). Monogamy can be interpreted in different ways and, in its “purest” form—having only one lifetime sexual partner—it offers almost 100% protection against STBBIs. The problem, however, is that most of us have more than one partner in our lives and adopt certain behaviours that expose us to increased risk:

• Our tendency to have sex before being “official” or without having had an explicit discussion about exclusivity.
• Our susceptibility to stop using condoms or dental dams when:
  • We want a “serious” relationship (Skakoon-Sparling & Cramer, 2020)
  • We want to increase trust and intimacy (Starks et al., 2018)
  • The risk of pregnancy is reduced (Morroni et al., 2014)
  • We think we’re safe even though we didn’t have an open discussion about sexual health and didn’t get tested (Sparling & Cramer, 2015).

Second, people in nonmonogamous relationships are more likely to adopt prevention strategies, such as condom use and frequent STBBI testing, than people in monogamous relationships (Lehmiller, 2015). A study comparing these two groups also found that people in monogamous relationships took fewer precautions to limit the transmission of STBBIs with their other partners (i.e., during infidelity; Conley et al., 2012).

Infidelity, the elephant in the room, is a relatively common behaviour that introduces the risk of contracting an STBBI.

According to one study, 21.2% to 31.8% of women and 36.6% to 52.8% of men in monogamous relationships have engaged in sexual activities involving a risk of STBBI transmission (oral sex, anal penetration, etc.) with someone other than their committed partner (Luo et al., 2010).

Thus, what exposes us to a risk of contracting an STBBI is more a failure to use protection than simply having several partners.

In recap…

Having multiple partners can be a risk factor for contracting an STBBI. After all, if you have no sexual contact whatsoever, the risk of contracting an STBBI is almost zero. The risk increases with the number of partners simply because the chances of coming across an infected person increase.

However, the belief that more sexual partners automatically leads to more STBBIs is a risk factor in itself, because it increases or maintains STBBI stigma, which does nothing to protect us from STBBIs. In fact, it can even increase our likelihood of avoiding condoms, getting tested, and having an open discussion about our sexual health, all of which can… increase STBBI rates.

So, if our goal is to decrease rates of STBBI transmission, it’s more effective to do the following things rather than perpetuate slutshaming and STBBI stigma by avoiding dating people who have or have had several partners:

1. Use barrier protection methods (condoms, dental dams, or latex gloves) consistently.
2. Use them until you have an open discussion about sexual health with your partner.
3. Use them until you get tested at a screening clinic like Prelib.