Rugby, a full contact sport, exposes participants to a high risk of injury. While several studies have explored injuries among male rugby players, few have investigated injuries among females. We conducted a cross-sectional study of United States of America (USA) female rugby players to assess the players' perception of foul play and the referee response to foul play and to evaluate the association between players' perception of foul play and injury. An anonymous, self-administered questionnaire reporting injury status, history of player perceived foul play and referee response was administered to 258 players recruited at a women's rugby tournament. The overall rate of injury was 4.4 injuries/100 matches, 0.2 injuries/100 practices and 1.4 injuries/100 total rugby exposures (matches and practices), with 107 (41.5%) players classified as injured. While 16.5% of players admitted to perpetrating foul play without an assessed penalty and 13.8% to being penalised for foul play, a smaller proportion reported being sent to the 'sin bin' (temporarily removed from play) or being ejected from a match (3.3% and 1.3% respectively). Of the 107 injured, 24.3% believed they had been injured as a result of foul play. Among all 258 players, self-perception of having been hurt due to unpenalised foul play was associated with study-defined injury (OR = 2.4, 95% CI = 1.0-5.9, p = 0.046). To make the sport safer, efforts should be made to minimise foul play. Suggested preventive methods include educating referees, coaches and players about the prevalence of foul play in women's rugby and the association between foul play and injury.