Silence kills. When is comes to relationships, the silent treatment does the most damage and is a death sentence to romance.

Paul Schrodt, professor and graduate director of communication studies at Texas Christian University, reviewed previous research data from over 14,000 participants of 74 studies, finding that the silent treatment is part of a "demand-withdraw" pattern that is a warning sign of a failing relationship.

The findings titled, "A Meta-Analysis Review of the Demand/Withdraw Pattern of Interaction and its Associations with Individual, Relational, and Communicative Outcomes," found that the behavior that will break a relationship occurs when one partner criticizes, complains, or demands constantly, causing the other partner to avoid, ignore and keep quiet.

"It's the most common pattern of conflict in marriage or any committed, established romantic relationship," says Schrodt. "And it does tremendous damage."

The research published in the March 2014 issue of the journal Communication Monographs, linked silent treatment behaviors to less satisfaction in a relationship, less intimacy and poor communication, making it the worst way to kill off a romantic relationship.

"It's a real, serious sign of distress in the relationship," he says.

A failure in communication is one of the worst factors that break up healthy relationships, but the silent treatment also causes other emotional and physical harm. Demand-withdraw behavior was linked to anxiety, aggression, urinary and bowel problems and erectile dysfunction.

Because old habits die hard, breaking this pattern is also not easy to do. "Partners get locked in this pattern, largely because they each see the other as the cause," says Schrodt.

Partners tend to blame the other as the problem, which causes further withdrawal. The research found that it did not matter who was demanding and who was withdrawing in the relationship. Regardless of the roles, the damage was still severe.