LAUSR

Premenopausal osteoporosis is not an infrequent cause of referral for clinical evaluation in younger women. Patients typically sustain one or more low-trauma fractures in unexpected circumstances. Further evaluation leads to bone density testing and basic laboratory assessment. There are many potential secondary causes of bone loss that may lead to fracture in youngerwomen, but the female athlete triad is an increasingly recognized cause in thosewhoparticipate in intense athletic activity, usually while still in school or while at university, but sometimes after university in women in the third decade who continue to pursue intense physical activity. The triad may be seen in ballet dancers, longdistance runners, or other athletes who restrict caloric intake to enhance performance. The female athlete triad classically includes restrictive eating, amenorrhea, and osteoporosis [1]. Restrictive eating leads to low energy availability, as does intense physical activity during training or competition [2]. Low energy availability may be associated with disordered eating or an eating disorder, but not always. Patients with the triad consequently have a low body mass index (BMI). This may lead to delayed menarche, and oligomenorrhea or amenorrhea associated with functional hypothalamic amenorrhea evidenced by low serum estradiol and gonadotropins [3], which leads to increased bone turnover and rapid bone loss. Patients typically have low bone mineral density (BMD) that eventually leads to stress reaction or fracture, commonly in the lower extremities [4,5]. According to the Female Athlete Triad Coalition [1], risk factors leading to the female athlete triad include at least one of the following “high risk” triad risk factors: DSM-5-diagnosed eating disorders; BMI ≤17.5 kg/m, body weight of <85% expected weight, or weight loss of >10% in one month; menarche at ≥16 years; current or past history of <6 menses over 12 months; two or more stress reactions or fractures, one high-risk stress reaction/fracture, or a low-energy non-traumatic fracture; or a bone density Z-score < −2.0. It may also be diagnosed with at least two “moderate risk” triad risk factors, including: disordered eating for ≥6 months; BMI between 17.5 and 18.5 kg/m, body weight of 85–90% expected weight, or recent weight loss of 5–10% in one month; menarche between 15 and 16 years; 6–8 menses over 12 months; one prior stress reaction/fracture; or BMD Z-score between −1.0 and −2.0. It may also be diagnosed with ≥1 nonperipheral or ≥2 peripheral, long-bone traumatic fractures if there are ≥1 moderate or high risk triad risk factors. The Coalition issued a Cumulative Risk Assessment for the Female Athlete Triad in its 2014 paper, to give a more objective way of determining an individual athlete's risk using risk stratification and evidence-based risk factors.