Deputies went to Mathis's home Friday in Manvel, about 25 miles south of Houston, after getting a 911 call. Erica Smith told deputies the player had pushed her onto a bed and started choking her. The 26-year-old woman refused medical treatment but said she is six months pregnant.
Mathis had left the house when deputies with the Brazoria County Sheriff's Department arrived. When he returned Sunday, he was arrested and charged with assault and family violence.
He was released on $3,000 bond. If convicted, he faces up to a year in jail and a fine of up to $4,000, authorities said. His attorney could not be immediately located.
In December, Mathis received a misdemeanor citation after his pit bull chewed through a fence and behaved aggressively.
The 24-year-old player was on the Texans' injured list last season.