High prevalence of subtle and severe menstrual disturbances in exercising women: confirmation using daily hormone measures

Abstract

This study suggests that approximately half of exercising women experience subtle menstrual disturbances, i.e. LPD and anovulation, and that one third of exercising women may be amenorrheic. Estimates of the prevalence of subtle menstrual disturbances in exercising women determined by the presence or absence of short or long cycles does not identify these disturbances. In light of known clinical consequences of menstrual disturbances, these findings underscore the lack of reliability of normal menstrual intervals and self report to infer menstrual status.

A longitudinal study of physical activity and menstrual cycle characteristics in healthy Norwegian women – The Nord-Trøndelag Health Study

“…Menstrual disturbances in highly active women have been suggested to reflect oestrogen deficiency due to low body weight, weight loss, or excessive exercise (25)(26)(27)45,46). In the current study, adjustment for BMI did not significantly alter the observed relationships between LTPA and menstrual cycle characteristics.…”

Current and past menstrual status is an important determinant of femoral neck geometry in exercising women

“…Self-reported current menstrual status was then confirmed prospectively by classifying menstrual cycles by length of the intermenstrual interval, the presence of menses, and characteristic reproductive hormone profiles [16]. These determinations were made from the measurement of daily urinary ovarian steroid metabolites, estrone-1-glucuronide (E1G) and pregnanediol glucuronide (PdG), as previously described [16,38].…”

“…These determinations were made from the measurement of daily urinary ovarian steroid metabolites, estrone-1-glucuronide (E1G) and pregnanediol glucuronide (PdG), as previously described [16,38]. E1G and PdG were measured in each urine sample using microtiter plate competitive enzyme immunoassays and a polyclonal capture antibody supplied by Coralie Munro University of California (Davis, CA) as previously reported [12,16].…”

“…Functional hypothalamic amenorrhea, defined as the absence of menses for greater than 90 days (secondary amenorrhea) [16] or the failure to attain menarche by age 15 (primary amenorrhea) [17] which cannot be explained by other underlying pathology [17], and oligomenorrhea, defined as irregular and inconsistent menses at intervals of 36 to 90 days [16], are the most severe presentations of menstrual cycle disturbances and are linked to poor skeletal health [3,5,8]. Low BMD in female athletes is defined as a Z-score between −1.0 and −2.0 in combination with a history of inadequate nutrition, hypoestrogenism, and stress fractures; whereas, the term "osteoporosis" is reserved for a BMD Z-score ≤ −2.0 with secondary risk factors for fracture [18].…”

Management of Low Bone Mass in Female Athletes

“…From delaying the onset of menarche 27 to causing subclinical menstrual disorders, oligomenorrhea, and amenorrhea, 28 exercise can impact menstrual function in several ways. Oligomenorrhea is defined as menstrual cycles occurring at intervals longer than 35 days, and secondary amenorrhea is defined as the absence of menstrual cycles for more than 3 months in a previously menstruating individual.…”