Amenorrhea refers to the absence of a menstrual period. Primary Amenorrhea is when a woman’s menstrual period has never begun (by age 15), while Secondary Amenorrhea is the absence of menstrual periods (for 3+ months) in a woman who was previously menstruating (Rinaldi). The most common kind of amenorrhea in athletes is known as functional hypothalamic amenorrhea (FHA).
Amenorrhea is often caused by the disruption in regulator hormones produced by the hypothalamus. The hypothalamus is the region of the forebrain that coordinates the automatic nervous system and the pituitary gland. The disruption in regulator hormones causes the pituitary gland to send signals to the ovaries that produce cyclic hormones (Rinaldi). This causes the absence of a period.
FHA is caused by low energy intake, exercise, weight loss, stress, or a combination of these factors and can affect athletes from every sport. Athletes engaging in high intensity and frequency of exercise are more prone to FHA (Gordon et al). The lower someone’s body weight is, the higher likelihood they will develop FHA. It does not mean FHA is exclusive to athletes with a lower body weight. FHA can affect women of all shapes and sizes (Gordon et al).
Many people believe it is normal for an athlete to stop menstruating during periods of heavy training. This is not true. Amenorrhea is NEVER normal for an athlete (Gordon et al). Amenorrhea is an indicator that your body does not have enough energy intake for all systems to function properly. It also is a sign that your body is overly stressed past an adaptive response and your body fat is lower than your body needs.
The most common complications of amenorrhea are osteopenia (a reduction in bone density) and osteoporosis (porous bones). These are complications of low estrogen levels seen in women with prolonged amenorrhea (Gordon et al). Estrogen, the hormone that helps regulate the menstrual cycle, is protective against bone loss. It is instrumental in bone formation and utilizes vitamin D, calcium and other hormones to effectively break down and rebuild bones (Gordon et al).
Higher rates of injury are seen in athletes who do not menstruate regularly. FHA is dangerous because the weakened bones dramatically increases risk of stress fractures and bone fractures. It is estimated that every year without a menstrual cycle, females can lose more than 2% of their bone density (Rosen). This bone loss is irreversible and the injuries resulting from low bone mineral density can sideline athletes permanently. Other long-term complications of FHA include infertility and premature aging.
Amenorrhea could be an indicator that one has relative energy deficiency in sport (RED-S), a common result of insufficient caloric intake and/or excessive energy expenditure (Mountjoy et al). RED-S concept has been adapted from a previously identified syndrome known as the Female Athlete Triad. RED-S causes changes in physiological systems, including metabolism, menstrual function, bone health, immunity, protein synthesis and cardiovascular and psychological health (Mountjoy et al).
Amenorrhea is also a common sign that there is a potential underlying body image or disordered eating behaviors that need to be addressed. Undernourished and over exercised young bodies are also very prone to injury and susceptible to eating disorders. By dieting, over-exercising, and engaging in disordered eating behaviors, athletes shorten their careers and are eight times more likely to get injured (Ziegler).
Amenorrhea is becoming increasingly common and it is important to break the silence. The cause of amenorrhea is different for each person but is always an indicator that something more serious is going on and should be brought up with your physician.
References
Gordon CM, Ackerman KE, Berga SL, Kaplan JR, Mastorakos G, Misra M, Murad MH, Santoro NF, Warren MP. Functional Hypothalamic Amenorrhea: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2017 May 1;102(5):1413-1439.
Misra M, Katzman D, Miller KK, Mendes N, Snelgrove D, Russell M, Goldstein MA, Ebrahimi S, Clauss L, Weigel T, Mickley D, Schoenfeld DA, Herzog DB, Klibanski A. Physiologic estrogen replacement increases bone density in adolescent girls with anorexia nervosa. J Bone Miner Res. 2011
Mountjoy M, Sundgot-Borgen J, Burke L, et al. The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S) Br J Sports Med 2014; 48: 491-497. Oct;26(10):2430-8.
Rinaldi, N. No Period Now What. Factors in a Missing Period Part 1. http://www.noperiodnowwhat.com/hypothalamic-amenorrhea-info/factors-in-hypothalamic-amenorrhea. (access on August 30, 2018).
Rosen, E. (October 10, 2018). Amenorrhea in female athletes: 8 myths debunked. Retrieved from http://www.gaudianiclinic.com/gaudiani-clinic-blog/2018/10/10/amenorrhea-in-the-female-athlete-8-myths-debunked
Ziegler, P.J., Khoo, C.S., Sherr, B., Nelson, J.A., Larson, W.M., & Drewnowski, A. (1998). Body image and dieting behaviors among elite figure skaters. International Journal of Eating disorders, 24, 4.