Biological anthropologist Helen Fisher of Rutgers University and evolutionary biologist Justin R. Garcia of The Kinsey Institute at Indiana University said the 2012 study was based on a survey of 5,481 U.S. singles and 1,095 married people ages 21-65.
The survey, sponsored by Match.com and conducted by MarketTools, found 47 percent of married people achieved orgasm 91 percent to 100 percent of the time when having sex, versus 38 percent of singles who reported reaching orgasm at that level.
More than 80 percent of married men and women said they would marry the same person again and 76 percent of married men and 73 percent women said they were still very much in love with their spouse.
Fifty-two percent of singles and 46 percent of married people go out one to three times a week, while 78 percent of married people and 55 percent of singles prepared home-cooked meals on a typical weeknight.
No further survey details were provided but Fisher said the sample was representative of the United States and was not of the match.com membership.