Virtually all American couples, married or cohabiting, expect sexual exclusivity of one another. This article asks why some people are sexually exclusive while others have sex with someone besides their mate. Previous research has linked personal values, sexual opportunities, and quality of the marital relationship to extramartial sex. This paper integrates these findings in a multivariate model that incorporates factors informing sexual decision making as well as demographic "risk factors." Nationally representative survey data show higher likelihood of sexual in, fidelity among those with stronger sexual interests, more permissive sexual values, lower subjective satisfaction with their union, weaker network ties to partner, and greater sexual opportunities. With these factors controlled, gender differences are substantially reduced or eliminated, although racial effects persist.
Key Words: Cohabitation, extramarital sex, marriage, sexual behavior.
Americans disapprove of sexual infidelity. More than 90% of the general public say it is "always" or "almost always" wrong for a married person to have sex with someone besides the marriage partner (Smith, 1994). About half the states in the U.S. retain laws against adultery that, although they are rarely enforced, would deny married persons who have extramarital sex the right to vote, serve alcohol, practice law, adopt children, or raise their own children (Constitutional barriers, 1992; Siegel, 1992). American couples, whether married or cohabiting, agree that it is important to be monogamous (Blumstein & Schwartz, 1983; Greeley, 1991).
Couples' agreements about sexual exclusivity are a contractual condition of their unions. As with all contracts, bargains are sometimes broken. Although sexual fidelity is the dominant practice, recent surveys show that between 1.5 and 3.6% of married persons had a secondary sex partner in the past year (Smith, 1991; Choi, Catania, & Dolcini, 1994; Leigh, Temple, & Trocki, 1993). This paper asks why some people are sexually exclusive while others have sex with someone besides their mate.
Research on sexual infidelity has focused on three domains-the personal values of the individual, the opportunities for extramarital sex, and the couple's relationship.
Permissive sexual values are associated with extramarital sex. Among Americans who believe extramarital relations are "not at all wrong," 76% report having had extramarital sex compared to only 10% of those who think extramarital sex is "always wrong" (Smith, 1994). Being male, African-American, and well educated are all associated with permissive sexual values (Smith, 1994). So is living in a big city. Extramarital permissiveness is linked to liberal political and religious ideologies (Smith, 1994). It is also related to gender egalitarianism and premarital permissiveness (Reiss, Anderson, & Sponaugle, 1980).
Opportunities, namely potential partners and circumstances assuring secrecy, facilitate extramarital sex. Some Americans admit they would have extramarital sex if their mate would not find out (Greeley, 1991). Couples who lead separate lives, for example, have more opportunities and are more likely to have secondary sex partners (Blumstein & Schwartz, 1983). Married people who perceive alternative partners to be available are more likely to have had extramarital sex (Johnson, 1970; Maykovich, 1976). Of course, those predisposed to extramarital sex might be more likely to recognize opportunities that arise.
Dissatisfaction with the marital relationship itself is associated with extramarital sex (Brown, 1991; Vaughn, 1986). Those who engage in adultery are less likely to report happy marriages (Greeley, 1991; Bell, Turner, & Rosen, 1975). Infidelity has been linked to men's sexual dissatisfaction (Maykovich, 1976) and to women's perception of inequity in the marriage (Prins, Buunk, & VanYperen, 1983). …