September 8, 2011
In a new study of more than 6,800 people in heterosexual and same-sex relationships, "all couple types reported substantially greater rates of monogamy in the year 2000 than in 1975," the authors wrote. "Our findings reveal a marked movement toward monogamy over time."
The researchers compared responses to questions covering a range of relationship issues from 6,082 people in 1975 and 782 in 2000. The questions were posed in the same way in both years. The answers revealed "dramatically less extra-relational sexual behavior" in 2000, said co-author Robert-Jay Green, PhD, a psychology professor at San Francisco's Alliant International University.
From 1975 to 2000, the proportion of persons who reported having sex with someone other than their main partner declined as follows: married heterosexual men, from 28 percent to 10 percent; married heterosexual women, from 23 percent to 14 percent; gay men, from 83 percent to 59 percent; and lesbians, from 28 percent to 8 percent.
As to why this occurred, the authors "speculate that awareness of HIV/AIDS and other STDs has led couples to be more cautious and more conservative about sex outside their relationships over the last 25 years." Green added it is also the result of society's growing acceptance of same-sex couples.
Emily Hecht-McGowan of the Family Equality Council, which promotes equality for LGBT families, agreed. "I think same-sex couples are more comfortable living openly in their communities and building families," she said.
The study, "Heterosexual, Lesbian and Gay Male Relationships: A Comparison of Couples in 1975 and 2000," was published in the journal Family Process (2011;50(3):353-376).