What Is Monogamy?

Medically Reviewed by Dan Brennan, MD on June 27, 2021

Monogamy is a relationship with only one partner at a time, rather than multiple partners. A monogamous relationship can be sexual or emotional, but it’s usually both. 

Many modern relationships are monogamous. But even if they want to be with just one partner, some people have trouble staying monogamous. This can lead to infidelity, separation, breakups, and divorce.

Studies in animals have shown that certain genes may be linked to monogamous behaviors. This could mean humans have evolved to prefer monogamy, seeking out one partner with whom we share most of our lifetime.

Other Names for Monogamy

You might also hear monogamy called:

But these terms could also reflect more nontraditional arrangements, such as an open relationship, in which one or both members are not monogamous and have other sexual or romantic partners. The word “exclusivity” may be more accurate than “monogamy,” since it suggests that both partners are seeing only each other.

Terms like “faithful” or “loyal” can also describe a partner in a monogamous relationship who hasn’t been unfaithful to the other person.

What’s the Difference Between Monogamy and Polyamory?

Monogamy means exclusivity in a relationship. Many religions support and sometimes require monogamy. The US federal government and all 50 states require monogamous marriages.

Polyamory is having more than one sexual or romantic partner. Polygamy is having more than one spouse.

There are types of polygamy. Polygyny is when a man has more than one wife, and polyandry is when a woman has more than one husband. Neither type is legal in the US.

How to Explore Monogamy with Your Partner

If you want to have a monogamous relationship, talk about it with your partner.

To avoid confusion and uncertainty, you should both be able to lay out expectations about what you want from the relationship and what you’re comfortable with.  

Monogamous couples may sometimes want sexual encounters with other people. Polygamous partners may often long for a more committed, exclusive relationship. There’s no right answer, it’s important to talk about these issues so both partners can agree about what they want from one another. 

Signs That Monogamy Is a Problem

Sometimes, it will be clear that monogamy isn’t working from the beginning of a relationship. Other times, it may take years to understand the issue. These red flags may signal a problem:

  • One partner feels strongly about exploring other or multiple relationships
  • One partner has been unfaithful
  • The couple can’t agree on boundaries
  • One or both partners aren’t bothered by the thought of the other being with someone else
  • One or both partners feel limited or trapped 

These issues can often be resolved, either in couples’ therapy or alone, but they could also be signs that you need a change.

WebMD Medical Reference


SOURCES: “Polygamy.”

Institute for Family Studies: “Is Monogamy Unnatural?”

Merriam-Webster: “Polyamory.”

Sexual Medicine Reviews: “Monogamy and Nonmonogamy: Evolutionary Considerations and Treatment Challenges.”

Scientific American: “Monogamy May Be Written in Our Genes.”

The Cut: “8 Signs a Monogamous Relationship Isn’t for You.”

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