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Heavy menstrual bleeding in athletes

An increasing proportion of athletes are female, yet the persistent issue of menstruation is rarely researched in the context of athletics. This study gets the ball rolling.

Study under review: The Prevalence and Impact of Heavy Menstrual Bleeding (Menorrhagia) in Elite and Non-Elite Athletes


Though it’s not openly discussed very often, heavy menstrual bleeding (HMB) affects roughly a quarter[1] of the female population and can have a negative impact on physical performance and general quality of life.

Assessing the true impact of HMB is difficult due to the lack of standardized and objective diagnostic measures. Definitions can include blood loss of more than 80 ml[2] per menstrual cycle, or subjective measures like excessive menstrual blood loss that interferes with a woman’s physical, social, or emotional quality of life. Different studies[1] have defined the condition as including two or more of the following criteria: passing of large blood clots, need for double sanitary protection, need for frequent (every two hours or less) changes of tampons and towels, the need for 12 or more sanitary items per period, and flooding through to clothes or bedding.

Regardless of the definition, increased menstrual blood loss will increase a woman’s risk of iron deficiency, and in turn, iron deficiency anemia. Iron is an essential mineral with roles in numerous biological processes including oxygen transport[3] and energy production. Menstrual bleeding, particularly when it is heavier than normal, is the most common cause of iron deficiency anemia[4] in women of childbearing age. Accordingly, a recent observational study[1] found that 63% of women with HMB reported being deficient in iron at some point.

Due to its important roles in oxygen transport and energy production, poor iron status can have a profound impact[5] on endurance exercise[6] performance. Figure 1 shows exercise-related factors that compound the risk of anemia in menstruating athletes, namely increased iron loss[7] through the GI tract, sweat, and foot strike hemolysis (destruction of red blood cells from the repeated shock and impact of long distance running).

Figure 1: Routes of iron loss for the endurance athlete

The prevalence and impact of HMB in females who exercise has yet to be determined. The aim of this current observational study was to determine the prevalence of HMB in exercising females, determine if it correlated with level of athletic performance, and better understand the perceptions of HMB among female athletes.

Heavy menstrual bleeding affects approximately 25% of women, and can have detrimental effects on iron status, and, in turn, endurance performance. The purpose of this study was to examine the prevalence and impact of heavy menstrual bleeding in elite and recreationally active females who exercise.

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