A growing number of young American adults are engaging in what’s called “stay-over relationships,” in which they spend three or more nights together each week while still having the option of going to their own homes, a new study shows.

“Instead of following a clear path from courtship to marriage, individuals are choosing to engage in romantic ties on their own terms without the guidance of social norms,” study author Tyler Jamison, a doctoral candidate in the human development and family studies department at the University of Missouri, said in a university news release.

“There is a gap between the teen years and adulthood during which we don’t know much about the dating behaviors of young adults. Stay-overs are the unique answer to what emerging adults are doing in their relationships,” she added.

There are a number of reasons for this growing trend in stay-over relationships, said Jamison, who interviewed college-aged adults in committed, exclusive relationships.

“As soon as couples live together, it becomes more difficult to break up,” she explained. “At that point, they have probably signed a lease, bought a couch and acquired a dog, making it harder to disentangle their lives should they break up. Staying over doesn’t present those entanglements.”

The couples in the study with stay-over routines were content in their relationships, but didn’t necessarily plan to move in together or get married.

“Many college-aged adults are students who will soon be facing a transition point in their lives,” Jamison said. “Most students do not have a definite plan for where they will live or work after graduation, and stay-overs are a way for couples to have comfort and convenience without the commitment of living together or having long-term plans.”

The study appears in the current issue of the Journal of Social and Personal Relationships.