The Role of Oral Contraceptive Pills for Athletes with Menstrual Cycle Disruption
A balanced debate
Team! This debate is escalating and today's post is an attempt to make sense of it all. As someone who makes a career of straddling the fence between medicine and women's athletic performance, I see the ravages of menstrual cycle dysfunction through every stage of female reproductive life - during her reproductive prime and beyond menopause. Enjoy! -Carla DiGirolamo, MD
For decades, female athletes have struggled with menstrual cycle dysfunction as a result of imbalances in training, nutrition, and recovery. A common cause of this imbalance is low energy availability (LEA) which when persistent, can lead to relative energy deficiency in sport (RED-S).
LEA and RED-S are seen across many different sports. In one study, the prevalence in gymnasts was 44.8%, soccer players, 33.3%, ballet dancers 22%, volleyball players, 20%, and often >50% in long endurance athletes. When LEA and RED-S persist, women can experience impaired physiological function in areas including metabolic rate, bone health, immunity, protein synthesis, cardiovascular health, and menstrual cycle dysfunction among others. This was previously known as the Female Athlete Triad.
The menstrual cycle is very closely tied to energy availability and the stress response system. This makes sense because the biological purpose of the menstrual cycle is to promote pregnancy, which is highly dependent on energy availability for the mother and fetus. When there is an imbalance in energy availability and expenditure, the menstrual cycle is turned off because it is unfavorable to become pregnant when there is not enough energy to feed the mother and fetus.
When menstrual cycles become irregular or stop completely, there are consequences that include infertility and when prolonged, bone loss and increased risk of fracture. The reason for this is that irregular or loss of menstrual cycles results in decreased cyclic exposure of the tissues (such as the bones) to estrogen. When bones “see” less estrogen, the balance in bone metabolism shifts away from bone building, which negatively impacts bone mineral density. This is especially critical in women < age 30 because this is the period of time when the skeleton is acquiring its peak bone mass - a major factor in a woman’s risk of osteoporosis and fracture as she ages.
Disordered eating and dysfunctional relationships with food are often a component of the LEA and RED-S seen in female athletes from a very early age. Another contributing factor is a lack of high-quality research on how best to fuel female athletes for peak performance. Applying training and fueling principles of male athletes to females has led to overtraining and under-fueling the female athlete and thus the alteration or loss of menstrual cycles - which in some circles is considered “normal” and even more tragically, an achievement.
When a female experiences a change or complete loss of her menstrual cycle, the first step is to identify the cause. It is fairly routine in gynecologic practice to perform examinations and laboratory testing to exclude medical causes of menstrual cycle changes. However, the athlete suffering from LEA or RED-S can be more elusive because test results often do not reveal this energy imbalance. Once medical causes have been excluded, this is often where providers will prescribe OCPs.
But this does a disservice to the athlete - because there is a whole other realm of “root cause” that extends beyond mainstream medicine and that is optimizing fueling, training, and recovery for the female athlete. For this reason, the athlete’s medical providers, trainers, and nutrition experts need to work collaboratively to resolve these imbalances and facilitate the return of regular menstrual cycle patterns. Sadly, this level of collaboration is not the norm.
Fortunately, an increasing amount of high-quality information and research is surfacing to inform coaches and trainers of how best to fuel and train female athletes to optimize performance and preserve menstrual function. When females experience changes in their menstrual cycles, they should inform their doctors and their coaches immediately so that the root cause of the change can be identified and managed.
However, managing the root cause of LEA and RED-S does not always work. As a fertility and menopause specialist, I have seen many retired collegiate and competitive athletes who are no longer subject to the rigors of training and competition but continue to have abnormal or absent menstrual cycles. These women struggle with infertility and in some cases, osteoporosis soon after menopause onset.
In gynecologic practice, it is common to prescribe oral contraceptive pills (OCPs) that contain an estrogen derivative and a progestin to “regulate” irregular menstrual bleeding patterns. There are 2 ways in which OCPs function. First, as a contraceptive, OCPs suppress or disrupt ovulatory function at the level of the pituitary gland, and the chronic progestin exposure thins the uterine lining creating an unfavorable environment for implantation of a conceptus. Second, OCPs create more regular bleeding patterns with the cyclic 3 weeks of exposure to estrogen and progestin, followed by a pill-free week where the absence of these hormones allows the lining of the uterus to shed.
Unpredictable bleeding patterns can be bothersome to women, so creating more predictable bleeding cycles can be favorable. As mentioned previously, long-standing absent or irregular menstrual cycles is a risk factor for developing osteoporosis later in life and can compromise bone health. OCPs have been used to provide regular exposure of estrogen to the bones which is thought to help prevent bone loss.
Although OCPs may generate more predictable bleeding patterns and provide bones with regular exposure to estrogen, they do not address the root cause of the cycle irregularity. This is where mainstream medicine gets tripped up because there is not a clear understanding among most general practitioners of LEA, RED-S, and optimizing female athletic performance.
Without question, OCPs should not be used as a “quick fix” to “regulate” menstrual cycles. Every last effort should be made to manage the athlete’s fueling, training, disordered eating patterns, and recovery to restore her menstrual function without the use of medications like the OCP that simply mask the problem.
But let’s not be so quick to demonize the OCP. As I mentioned previously, excluding medical causes and optimizing fueling, training, and recovery does not always normalize the menstrual cycle. Once these efforts have been exhausted, treatment with OCPs is often considered in an effort to mitigate the risk of future bone loss, osteoporosis, and fracture. For the athlete who wishes to pursue pregnancy, there are very effective treatments that help restore ovulation and achieve pregnancy.
The notion that OCP use in younger women can prevent bone loss and reduce fractures is controversial. There are no high-quality randomized controlled trials that definitively argue for or against this in younger women with menstrual cycle dysfunction. However, for young women with hypoestrogenism due to primary ovarian insufficiency or premature menopause, hormone therapy is essential for mitigating the risks of bone loss, dementia, and cardiovascular disease.
Although the physiology of premature ovarian insufficiency is different from hypoestrogenism due to other causes, the study of this population underscores the risk of bone loss and other chronic conditions that can occur with chronic menstrual cycle absence or dysfunction. One could further argue that women with LEA and RED-S are at even greater risk of bone loss than women with POI due to the additional struggle with metabolic imbalances and reduced protein synthesis.
Once every effort to balance training, nutrition, and managing disordered eating patterns and recovery has been exhausted without the return of normal menstrual patterns, it is reasonable to consider treatment with OCPs to mitigate the risk of future bone loss, osteoporosis, and fracture.
Another treatment that is worth considering is the use of low-dose estradiol patches for bone protection in young female athletes with menstrual dysfunction. There are favorable data from studies of menopausal women showing that ultra-low doses of estradiol can afford significant bone protection. However, these studies may not necessarily be translated to the reproductive-age population. The loss of cyclic estrogen in menopausal women and the loss of cyclic estrogen in young female athletes are two very different physiologic scenarios. Certainly, low-dose estradiol treatment is worth studying in these young female athletes given the scope of the problem in this population.
Here are the key takeaways for the role of OCPs in young athletes with menstrual cycle dysfunction.
Prolonged irregularity or absence of menstrual cycles in young women - regardless of cause - is a known risk factor for developing osteoporosis later in life.
LEA and RED-S are common causes of menstrual cycle dysfunction in female athletes.
Laboratory evaluation may exclude medical causes but may not reveal energy imbalances of LEA and RED-S. For this reason, collaboration among medical providers, trainers, and nutritionists is paramount for optimal care of the female athlete.
Effectively managing the root cause of the energy imbalance is critical for preserving the female athlete’s health and achieving optimal physical performance.
Do not demonize the OCP! Despite best efforts for managing training, nutrition, recovery, and excluding medical causes, restoration of menstrual function may not happen. For these women, it is reasonable to consider OCPs in an effort to provide protection against bone loss, osteoporosis, and fracture given the benefits of hormone therapy seen in the POI population. That being said, randomized controlled trials in young women with refractory menstrual cycle dysfunction have yet to prove benefits for mitigating bone loss and preventing fracture.
More study is needed on the use of ultra-low-dose estradiol patches for bone protection in young female athletes with menstrual cycle dysfunction.
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Mountjoy M et al: 2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med 2023;57:1073–1097. doi:10.1136/bjsports-2023-106994
COMMITTEE OPINION #634 2015: The American College of Obstetricians and Gynecologists: Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign
COMMITTEE OPINION #698 2017: The American College of Obstetricians and Gynecologists: Hormone Therapy in Primary Ovarian Insufficiency
COMMITTEE OPINION #740 2018: The American College of Obstetricians and Gynecologists: Gynecologic Care for Adolescents and Young Women with Eating Disorders
NAMS Position Statement Management of osteoporosis in postmenopausal women: the 2021 position statement of The North American Menopause Society; Menopause 28(9) 2021. DOI: 10.1097/GME.0000000000001831