Is It OK for Athletes to Lose Their Periods?

Alexa Nikolai
Oct 15, 2025
4 min read

Overview

Today, over 3 million girls compete in high school sports, which is ten times as many as participated in the 1970s. As this number continues to grow, it is essential to ensure that young athletes are training as safely as possible, so they can have long and successful athletic careers and lives. In previous posts, we’ve discussed the dangers of energy deficiency in female athletes and types of sports injuries that are more prevalent in women.

In this post, we will be examining a common misconception: that it is ok and normal for female athletes to lose their periods. Rather, the menstrual cycle is an important indication of overall health and provides feedback about nutritional patterns, training intensity, and bone health. Losing your period is therefore a sign that your body is experiencing excessive stress and should be investigated, not ignored.

Why do female athletes lose their periods?

The term for losing your period due to excessive training, insufficient nutrition, or high stress is hypothalamic amenorrhea. In this condition, hormones that are normally produced in the brain and signal hormones in the ovaries are not produced. The exact reason for this stopped production is not clear, but it could be related to body fat percentage, weight, or cortisol levels, among other factors.

Hypothalamic amenorrhea occurs because it is evolutionarily protective. Essentially, your body is recognizing that you don’t have enough energy to support your own basic functions as well as develop a fetus, so ovulation stops in order to prevent pregnancy. This adaptation would have allowed our ancestors to retain their energy during periods of high stress or low food availability. However, today, that signal is often confused by other stressors, such as high levels of athletic training.

How common is it for athletes to lose their periods?

An estimated 25% of elite female athletes and 44% of women who exercise vigorously report chronically missing their periods, compared to 2-5% of the general population. Furthermore, although amenorrhea is the most severe case, up to 80% of women who exercise vigorously may exhibit some sort of menstrual dysfunction.

Amenorrhea is particularly common in sports that emphasize leanness, such as gymnastics, running, figure skating, and lightweight rowing, as athletes may feel pressure to eat less to stay lighter. The problem is further advanced because many athletes don’t know the risks of amenorrhea and are instead taught that it’s a normal side effect of athletic activity.

Why does losing your period matter?

In fact, amenorrhea is something to be concerned about because it is often a sign of Relative Energy Deficiency in Sport (REDS), a nutritional deficit that leads to poor health and declining athletic performance. Furthermore, a regular menstrual cycle, particularly during your twenties, is essential for bone health. Healthy levels of estrogen and other hormones that cycle during the menstrual cycle help build strong bones. Since bone mass and density tend to build during your twenties and peak around age thirty, losing your menstrual cycle during your teens or twenties can lead to low levels of estrogen and thus thinner bones and increased risk of osteoporosis. In the short term, even before REDS may fully develop, amenorrheic athletes are 2-4 times more at risk for stress fractures.

Although there may be less harmful reasons for occasionally missing your period (especially in the first few years after puberty), if you have not gotten your period by age 15 or within five years of breast development or if you miss three or more periods in a row, you may be experiencing hypothalamic amenorrhea.

Does menstruation affect athletic performance?

Although loss of blood during your period may make you feel more tired or weak for a few days, there is no evidence that athletic performance is decreased by a healthy normal cycle. Beyond basic convenience, then, there is no positive reason to miss your period as an athlete.

What should athletes do if they lose their period?

Fortunately, hypothalamic amenorrhea is typically reversible. If you do miss three cycles in a row, you should assess your levels of activity and fueling and consult with your doctor. Although it is usually possible to get your period back through dietary and activity adjustments, the long-term effects on bone health may not be reversible, so it is best to address the issue as soon as you are aware of it.

What about athletes on hormonal birth control?

Hormonal birth control can make it more difficult for athletes to use their period as a marker of good training and fueling balance. Birth control pills prevent natural periods from occurring: the “period” you get on birth control pills is actually a withdrawal bleed and does not indicate normal hormone levels and menstrual cycling. Hormonal IUDs do not provide a faux period, but they may lead to missed periods. In either case, the disruptions from hormonal birth control methods can mask cases of hypothalamic amenorrhea. For this reason, athletes on birth control pills or who have a hormonal IUD will have to monitor other vital signs to find evidence of overtraining or under-fueling.

Summary

Although sometimes they can be inconvenient, regular periods are an indicator of a healthy functioning body. Losing your period due to athletic training is not normal and not healthy and should be avoided. Especially if you participate in sports that require a low body weight, make sure you are eating enough to fuel yourself. If you do notice that you are beginning to miss your period, speak to your doctor and come up with a plan to make sure you are taking care of your body and your bones while you pursue your athletic endeavors.