• Unfaithfulness;   • Sexual Dysfunction;   • Major
Cardiovascular Events;   • Psychobiological Correlates    Aim. 
To offer a summary of available data in literature about
unfaithfulness.  Method.  An extensive Medline search was
performed including the following words
“unfaithfulness,”“extramarital affairs,”“infidelity,”“men.” The
search, up to December 4, 2011, was restricted to English-
language articles.  Main Outcome Measures.  We reported
literature data on the prevalence of unfaithfulness and on
related psychobiological, sexual, and risk factors.  Results. 
Some surveys reported that 1.5–4% of married men had
extramarital coitus in any given year, others that 23.2% of men
have cheated during their current relationship. Different
studies reported a lifetime prevalence of unfaithfulness between
15% and 50%. With respect to factors related to unfaithfulness,
several authors reported that men with extramarital affairs more
frequently have a dysfunctional primary relationship, in both
relational and sexual