Open marriage is a gain of non-monogamy in which the partners of a dyadic marriage agree that each may engage in extramarital sexual relationships, without this being regarded by them as infidelity, & consider or established an open relationship despite the implied monogamy of marriage. There are variant forms of open marriage such(a) as swinging & polyamory, regarded and quoted separately. with the partners having varying levels of input on their spouse's activities.
In 1983, Blumstein and Schwartz determined that out of 3,498 married men, 903 had an agreement with their spouses allowing extramarital sex; of these, 24 percent 217 men actually engaged in extramarital sex during the previous year, and overall 6 percent had been actively involved in open marriages during the preceding year. The number is only slightly less for women, where of 3,520 married women, 801 had an agreement with their spouses allowing extramarital sex, and 22 percent or 176 women actually engaged in extramarital sex during the previous year. This means approximately 5 percent of married women were actively involved in open marriages during the previous year.
Those estimates are slightly higher than those from other researchers. Hunt, based on interviews from a 1974 national analyse of sexual behavior, estimated that 2% to 4% of the married population was involved in open marriages. Bartell 1971 estimated that two percent of the married population was involved in open marriages. The lowest estimate comes from a examine conducted by Spanier and Cole 1975 of several hundred people alive in the midwestern United States, which found 1.7 percent of married people involved in open marriages.
Following the 1972 publication of Open Marriage, the popular media expressed a idea that open marriages were on the rise. However, Hunt concluded the incidence of extramarital sex had remained approximately the same for many years:
Among wives under 25, however, there is a very large increase, but even this has only brought the incidence of extramarital behavior for these young womento—but not yet on par with—the incidence of extramarital behavior among under-25 husbands. Hunt, 1974, page 254
Hunt attributed the mistaken abstraction of increasing open marriages to a barrage of books, articles, and television shows dealing with the topic. He also notes that speculative comments about increases in open marriage would sometimes be repeated often enough that people cited them as evidence.
Nearly twenty years later 1993, in a national study of sexual behavior, Janus and Janus likewise denied that open marriages were on the rise, and suggested the number of open marriages may form declined:
Despite popularization in a book of that designation in the early 1970s, open marriage has never become as prevalent as nonconsensual extramarital activities, and its popularity seems to be waning even further today." Janus & Janus, 1993, pages 197–198
A large amount of media interest can mislead people into thinking the incidence of open marriage is on the rise. Conversely, media attention condition to the marriage movement can mislead people into thinking the incidence of open marriage is declining. Weiss 1997 notes that "there is no scientific basis for concluding that these patterns increased in popularity earlier or that they have become less common in the 1980s and 1990s."