teen holds up calendar with marked days showing period tracking

General Health & Wellness • Aug 31, 2021

No Period, No Problem? | When to Worry About Your Teen Athlete’s Missing Menstrual Cycle

While many teenagers would gladly not experience a menstrual period each month, for pediatricians taking care of them, regular periods provide an important clue about the health and growth of adolescents.  For some athletes, intense training without adequate energy intake can lead to a well-known syndrome called Relative Energy Deficiency in Sports (formerly called the Female Athlete Triad).  The classic triad includes disordered eating, lack of menstrual periods for at least three months, and low bone mineral density.  Teens with this syndrome are at risk of persistent eating disorders, stress fractures, and also long-term impacts on bone strength.

Food is fuel

Often the triad starts with a young woman trying to become fit for her sport.  The risk for developing this syndrome is higher in endurance and aesthetic sports such as running, gymnastics, swimming, diving, figure skating, and dancing.  In many athletes, decreased food intake is unintentional.  Appetite suppression is often a result of intense exercise and decreased caloric intake because time constraints are common in adolescents.  Some teens may also engage in over-exercising to “get rid” of perceived excess caloric intake.  In either case, the common issue of not fueling with adequate calories leads to a negative energy balance.

A missing period might mean low estrogen levels in your teen

When this energy imbalance occurs, the hormones from the hypothalamus that regulate periods are disrupted and infrequent/irregular or absent periods result. Estrogen levels are affected, and this is critical because of estrogen’s effect on bones. Estrogen both stimulates bone formation and protects the skeleton from bone resorption. When there is not enough estrogen to allow for normal menses, there is not enough estrogen to stimulate normal increases in bone mineral density.

During young adulthood, women are forming most of their bone mass. This makes a lack of periods during this window of growth especially harmful.  Eventually, stress fractures may result.  This syndrome can also occur in adolescent males. You should suspect Relative Energy Deficiency in Sports when any teen athlete has a stress fracture.

Early recognition and intervention are key so ask your pediatrician if you have concerns.  For all you athletes with uteruses out there, it turns out you should be glad for the (menstrual) pad!