The study was referenced. Here is the reference:
Although extramarital sex may be the marital activ-
ity most often cloaked in secrecy, empirical estimates of affairs over the
course of a marriage range from 30 to 60% for men and from 20 to 50% for
women (Glass & Wright, 1992; Kinsey, Pomeroy, & Martin, 1948; Kinsey,
Pomoroy, Martin, & Gebhard, 1953; Hunt, 1974; Athanasiou, Shaver, &
Tavris, 1970; Levin, 1975; Petersen, 1983). Estimates of the combined prob-
ability that at least one member of a married couple will have an affair over
the course of a marriage range from 40 to 76% (Thompson, 1983). Estimates
of infidelity over the course of a single year of marriage, however, obviously
yield lower estimates such as 5% (e.g., Greeley, 1991). A conservative inter-
pretation of these figures suggests that although perhaps half of all married
couples remain monogamous, the other half will experience an infidelity over
the course of a marriage. Thus, a critical theoretical and practical issue is
what predicts who has affairs and who remains maritally faithful.
Gender is the most consistent previously established predictor of infidelity.
As the above statistics indicate, more men than women have affairs. Among
those men and women who do have affairs, men typically have affairs with
a greater number of partners than do women (Lawson, 1988). Men who have
affairs are more likely to do so without emotional involvement, whereas
women’s affairs are more often accompanied by emotional involvement
(Blumstein & Schwartz, 1983; Glass & Wright, 1985). Gender is also linked
with the sequelae of infidelity. A woman’s infidelity is more likely to lead
to divorce than is a man’s infidelity, across a variety of cultures (Betzig,
1989). Women whose husbands have affairs report that they are more willing
to forgive their partner than are men whose wives have affairs (Lawson,
1988). Finally, men are more likely than women to see their own extramarital
sex as justified and experience less guilt when they engage in it (Johnson,
1970; Athanasiou et al., 1970; Spanier & Margolis, 1983).
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