Impact of Concussions on Menstrual Cycles in Young Women

Understanding the HPO Axis

Young women who experience concussions during adolescence may face dysfunction in their hypothalamic-pituitary-ovarian (HPO) axis, which can result in abnormal menstrual cycles. In the United States, approximately 1.9 million children under the age of 18 suffer from sport or recreation-related concussions each year.

Gender Differences in Concussion Effects

Statistics indicate that girls are more likely to sustain sport-related concussions, report more severe symptoms, and experience longer recovery times than boys participating in similar activities. The differences in post-concussion experiences between genders are believed to stem from variations in physiology, neuroanatomy, and hormone levels, particularly estrogen and progesterone.

The Role of the Menstrual Cycle

The menstrual cycle in females is regulated by the HPO axis, and any disruption in this system can lead to irregularities in menstruation, including conditions such as amenorrhea (cessation of menstruation) and oligomenorrhea (infrequent menstruation). It is critical to recognize these irregularities in adolescent girls, as they can lead to low estrogen levels and a decrease in bone mineral density.

Importance of Early Identification

If concussions impact the HPO axis and result in abnormal menstrual cycles, early identification of post-concussive symptoms could aid clinicians in managing menstrual irregularities in affected individuals.

Study Overview

Research Objectives

A study published in JAMA Pediatrics aimed to explore the relationship between concussions and the occurrence of abnormal menstrual cycles in young women. The researchers hypothesized that adolescent females who suffer concussions would exhibit a higher likelihood of experiencing irregular menstrual bleeding patterns compared to those with sport-related orthopedic injuries.

Methodology

To investigate this association, Snook and colleagues analyzed the menstrual patterns of 128 young women aged 12 to 21. This group included 68 individuals with sport-related concussions and 60 with sport-related orthopedic injuries. Participants were recruited from the University of Pittsburgh Medical Center Sports Concussion Clinic and Center for Sports Medicine, based on specific criteria which included being at least two years post-menarche, having regular menstrual cycles in the past year, and being English-speaking with smartphone access.

Participants received weekly automated text messages that contained a link to an online Qualtrics survey. This survey collected data on menstrual bleeding episodes, new injuries, use of hormonal contraception, and potential pregnancy status. Follow-up text messages were sent for up to 120 days post-injury, corresponding to approximately 3 to 4 menstrual cycles for each participant.

Research Findings

The primary focus of the study was to identify the development of abnormal menstrual patterns following a concussion. Researchers defined dysfunction by observing two or more of the following indicators: intermenstrual intervals of fewer than 21 days, intervals longer than 35 days, bleeding lasting less than 3 days, or bleeding extending beyond 7 days.

Of the 68 participants who sustained concussions, 16 reported experiencing abnormal menstrual cycles during the study period, while only 3 out of the 60 participants with orthopedic injuries reported similar issues. The findings suggest a significant correlation between concussions and the risk of developing abnormal menstrual patterns in young women.