Marta Meana of the University of Nevada at Las Vegas spelled it out simply in an interview with me at the annual Society for Sex Therapy and Research conference in 2017. “Long-term relationships are tough on desire, and particularly on female desire,” she said. I was startled by her assertion, which contradicted just about everything I’d internalized over the years about who and how women are sexually. Somehow I, along with nearly everyone else I knew, was stuck on the idea that women are in it for the cuddles as much as the orgasms, and—besides—actually require emotional connection and familiarity to thrive sexually, whereas men chafe against the strictures of monogamy.

But Meana discovered that “institutionalization of the relationship, overfamiliarity, and desexualization of roles” in a long-term heterosexual partnership mess with female passion especially—a conclusion that’s consistent with other recent studies…

Many women want monogamy. It’s a cozy arrangement, and one our culture endorses, to put it mildly. But wanting monogamy isn’t the same as feeling desire in a long-term monogamous partnership. The psychiatrist and sexual-health practitioner Elisabeth Gordon told me that in her clinical experience, as in the data, women disproportionately present with lower sexual desire than their male partners of a year or more, and in the longer term as well. “The complaint has historically been attributed to a lower baseline libido for women, but that explanation conveniently ignores that women regularly start relationships equally as excited for sex.” Women in long-term, committed heterosexual partnerships might think they’ve “gone off” sex—but it’s more that they’ve gone off the same sex with the same person over and over.