The phrase "an often contentious" is correct and usable in written English.
It can be used to describe a situation, topic, or relationship that frequently leads to disagreement or conflict.
Example: "The debate over climate change policies has become an often contentious issue among lawmakers."
Alternatives: "a frequently controversial" or "a regularly disputed".
But Mr. Schwartz has also had an often contentious relationship with the Legislature.
She brings a careful, nuanced and thoughtful approach to an often contentious subject.
Here in the Holy Land, religion is an often contentious matter.
The wrangling over the building is part of an often contentious history between the university and the surrounding community.
Typically, Chinese state firms bring most of their own workers for construction projects, an often contentious practice.
Sepp Blatter, the embattled president of FIFA, endured more than 30 minutes of questions, many of which he deflected, during an often contentious news conference Monday in Zurich.
The parties released a joint written statement, capping an often-contentious negotiation with a unified voice.
It was the absence of rancor that seemed most notable — the first faint sign of hope in an often-contentious 10-week standoff.
That said, there are clear dangers for Mr. Obama as well, not least of them any lingering rivalry between the two of them after an often-contentious primary campaign.
John Glenn, a Democrat who had an often-contentious relationship with Mr. Metzenbaum when both were senators from Ohio, said in an interview with The Columbus Dispatch in 1994: "I've worked with Howard Metzenbaum, and I've worked against Howard Metzenbaum.
Millions of dollars in repairs are still needed and an often-contentious battle to fix the building has strained the library administration's relations with both its employees and with City Hall.
