Preliminary Evidence for a Window of Increased Vulnerability to Sustain a Concussion in Females: A Brief Report

Abstract

A difference exists between sexes for the incidence of concussion injuries and severity of post-injury outcomes with females having a higher incidence rate (in comparable sports) and experience more robust symptoms than males. The basis for this disparity has remained largely unresolved. Recent findings point to a potential biological mechanism that may be related to the menstrual cycle as an arbiter of post-injury outcomes. What has not been addressed, is whether the phase of menstrual cycle (inferred fluctuations of ovarian hormones) contributes to an increased vulnerability to sustain a concussion injury. This prospective, observational study sought to determine if concussions occurred at different frequencies throughout the phase of the menstrual cycle. Female athletes who sustained a concussion injury were queried three times over the 7-day study (e.g., within 48 h of injury, and 4 and 7 days after injury) to recall the number of days that have elapsed since the beginning of their most recent menstruation. Twenty female athletes enrolled after sustaining a concussion; 18 were eumenorrheic and 2 amenorrheic. Among eumenorrheic participants at the time of injury, 2 were in the follicular phase, 4 were in the early luteal phase and 9 were in the late luteal phase. Two athletes were injured on the first and 1 was injured on the second day of menstruation. The greatest number of concussions were sustained during the late luteal phase and during the first 2 days of menstruation. This 9-day window accounted for 2/3rd of the sustained concussions in our study.

Influence of Sociodemographic, Premorbid, and Injury-Related Factors on Post-Concussion Symptoms after Traumatic Brain Injury

“…This may also be related to changes in the endocrinal levels in both males and females. With increasing age, these changes may influence mood, strength, and quality of life [ 58 , 59 ] and recovery processes after TBI [ 60 ], and thus may lead to the observed differences between the sexes. Changes in social roles with aging may have an impact on the experiencing of PCS [ 61 ].…”

Under-representation of female athletes in research informing influential concussion consensus and position statements: an evidence review and synthesis

“…23 Lower cervical strength relative to head mass among female athletes suggests differing head impact biomechanics may influence concussion. 24 Hormone levels may even create concussion-specific vulnerability windows, 25 while also complicating the clinical assessment 26 and implicating biological sex as a factor in concussion vulnerability. Within the sociocultural realm, female athletes have generally shown greater willingness to report concussions or symptoms [27][28][29] that could impact nearly every self-report measure in concussion and implicates gender-driven acculturation as a factor in recovery.…”