In Reply We thank Benvenga et al for their thoughtful commentary on our article1 examining abnormal menstrual patterns in adolescents and young women after sport-related concussion. These authors discuss several key issues related to our article including references, mechanisms for our findings, and future research. The references2,3 noted by the authors and not included in our article represent significant contributions to the literature detailing the association of severe traumatic brain injury (TBI) and hypopituitarism. However, we noted differences between the patients in these case series and those from our study. Specifically, approximately half of the patients2,3 were male, most were either prepubertal or adult, and experienced severe, non–sport-related TBI. Yet the results from these studies are applicable to our study. By demonstrating pituitary dysfunction using hormonal assessment, Acerini et al2 reported gonadotropin deficiencies in 80% (n = 16 of 20) of pediatric patients following severe TBI. All 3 of the female adolescents with severe TBI (skull fractures) in these series2,3 exhibited gonadotropin deficiencies 2 to 5 years after injury, and at least one reported amenorrhea. These findings suggest that gonadotropin deficiencies may be a long-term consequence of TBI. Perhaps, as we stated in our article, “more subtle forms of brain injury, such as concussion, may adversely affect HPO [hypothalamic-pituitary-ovarian] axis function…leading to disrupted gonadotropin secretion.”1