Is Infidelity a Cause or a Consequence of Poor Marital Quality?

Abstract

Because sexual fidelity is a key norm regulating the institution of marriage, any occurrence of extramarital sex (EMS) could potentially contribute to marital dissolution. Although the relationship between EMS and marital dissolution has been demonstrated in past research, studies have yet to show if the occurrence of EMS causes a marriage to break down, or if an unraveling marriage prompts spouses to seek alternative sexual partners. In this 17-year longitudinal study ( N= 1,475), we assessed whether EMS precedes or follows deteriorations in marital quality. We estimated the effects of marital happiness and divorce proneness on EMS, the effects of EMS on subsequent marital happiness and divorce proneness, and the effects of all three variables on divorce. Our results indicate that divorce proneness predicts the occurrence of EMS. Results also suggest that EMS lowers subsequent marital happiness, increases subsequent divorce proneness, and increases the odds of divorce. We conclude that infidelity is both a cause and a consequence of relationship deterioration.