690 FO53 – Tackling female health in rugby, one cycle at a time: the association between menstrual cycle regularity and concussion history

Background Concussions are the most common injury in female rugby union. Due to the increased popularity of women's rugby, it is important to ensure female-specific factors are considered, including the menstrual cycle. Function of the pituitary axes have been reported to be affected following concussion, which may contribute to irregular menses and greater concussion-like symptoms. Objective The objective of this study was to evaluate the association between previous concussion history and irregular menses in female rugby union players. Design Cross-sectional study within cohort studies. Setting Youth, varsity, and professional female rugby leagues in Canada, Ireland, and South Africa. Participants Female rugby players participating in one of two prospective cohort studies (Ireland, South Africa; ages 18–39 or Canada; ages 11–18) were included. Assessment of Risk Factors The association between self-reported previous concussion history (yes/no) and reports of irregular menses was evaluated using multivariable logistic regression (adjusting for cluster by team). Main outcome measurements Self-report of regular menses (yes/no). Results A total of 278 players [116 adolescents (median age=17.16; IQR:16.91–17.59)) and 180 adults (median age=18.97; IQR:18.47–19.50)] rugby players participated. A total of 99/278 players (33.56%) reported a previous concussion history and 53/278 (17.97%) reported irregular menses. In adult players, there was a 2.17-fold (95%CI 1.02–4.62) greater odds of reporting irregular menses in players with a previous concussion history relative to players without a previous concussion history. There was no difference in adolescent players [ORadolescent=0.56 (95% CI 0.15–2.13). Conclusions Adult rugby players with a concussion history have greater odds of reporting irregular menses. The relationship between menstrual cycle irregularity and concussion risk requires further evaluation using a prospective cohort design. These study findings highlight the importance of sex-specific considerations in concussion prevention and potentially recovery following concussion.