Infidelity

Gender differences in sexual attitudes and behavior are striking. Compared to men, women are less accepting of extensive sexual experience, non-marital coitus, and casual sex outside a committed relationship. Sexual behavior is consistent with Sexual exclusiveness is strongly related to marriage stabil ity. Women consider infidelity to be a greater threat to marriage than do men. HELEN KING/CORBIS sexual values. Wives are less likely than husbands to engage in extramarital sex. Apparently, this is due largely to attitudes: Controlling for permissiveness of sexual values and for the frequency of sexual thoughts largely eliminates the gender difference in the likelihood of sexual infidelity (Treas and Giesen 2000). Although men are willing to consider sex without emotional commitment, women view romantic attachment as a prerequisite for sex. Hence, women regard sexual infidelity as a greater threat to marriage than do men (Blumstein and Schwartz 1983; Wellings et al. 1994). When asked what might justify extramarital sex, women are more likely than men to invoke falling in love and less likely to cite sexual gratification.

One explanation for gender differences in sexual behavior frames an evolutionary argument: Men's genetic legacy is maximized when they impregnate many women while women's optimal reproductive strategy calls for breeding selectively with men who will help to raise the children. Other explanations emphasize social roots of monogamy such as the gendered nature of learned scripts explicitly motivating sexual activity.

For both men and women, normative beliefs and behavioral patterns seem to be established by late adolescence and early adulthood. In the early teen years, girls' peer groups are already reinforcing monogamous feeling norms (e.g., don't have romantic feelings for a boy who has a girlfriend or for more than one boy at a time). Even in adulthood, sexual attitudes continue to reflect the values of the community in which one was raised. Early experience foretells later behavior. According to French survey data, the younger the age at first intercourse, the more likely an individual living in a couple relationship is to have multiple sexual partners (Bozon 1996). In the United States, having had more sexual partners before the first marriage or cohabitation also increases the likelihood of infidelity (Treas and Giesen 2000). The implication seems to be that premarital sexual lifestyles encourage infidelity in marriage, but some unidentified common factor (e.g., a preference for risk-taking behavior) may account for sexual behavior both before and during marriage.

Individuals who strongly disapprove of extramarital sex are not likely to be unfaithful. The personal discomfort in violating deeply held values discourages infidelity, although those who are unfaithful may also work to bring their values in line with their behavior (Lawson 1988). Most organized religions teach values that emphasize sexual fidelity. People who attend religious services are less likely to engage in infidelity, even when the individual's sexual values are taken into account (Treas and Giesen 2000). Belonging to a community that is supportive of sexual fidelity seems to discourage extramarital sex—above and beyond any influence on individual moral beliefs.