Complex sentence: On December 7,2017 St-Pierre announced that he vacated his UFC middleweight title after 31 days of winning the belt, suffering from colitis, to avoid holding up the middleweight division.
Split into simpler sentences: On December 7,2017 St-Pierre announced that he vacated his UFC middleweight title after 31 days of winning the belt. Suffering from colitis, St-Pierre wanted to avoid holding up the middleweight division.