The effect of levonorgestrel-releasing intrauterine device in sport performance among young athletes from Brazilian Paralympic Athletics Team.
Authors: DE ARAUJO MAITA POLI , Depes Daniella De Batista , Lourenço Thiago , Melloni Mauro Augusto Screiter , Silva Hesojy Gley Pereira Vital da , Júnior Gil Guerra , de Carvalho Poliana Caroline 
Published: January 2025

Introduction: The use of highly effective contraceptives could be a health measure for Paralympic athletes and may potentially have a positive impact on sports performance.
Objectives: To describe the effect of the levonorgestrel-releasing intrauterine device (IUD-LNG) on sports performance indicators in Paralympic athletes.
Methods: A prospective, non-randomized, descriptive study was conducted with 10 Paralympic athletes, aged between 18 and 25 years, who chose the levonorgestrel-releasing intrauterine device (Kyleena®, Bayer HealthCare Pharmaceutical Inc., Wayne, NJ, USA) as a contraceptive method. Pain scores during insertion were assessed using the Visual Analog Scale (VAS). The main performance indicators studied were: motor variables (isokinetic test, 50-meter sprint, and vertical jump), somatic variables (body composition and bone mineral density), and health variables (menstrual bleeding pattern, blood levels of hemoglobin, iron, and ferritin). Motor and health variables were measured before insertion and every four months. Menstrual bleeding patterns were classified as favorable or unfavorable. Body composition values before device insertion were compared with values after one year of use. The sample was non-probabilistic, for convenience. Data were described as means and standard deviations. Comparisons between periods regarding measured variables were performed using the Friedman or Wilcoxon test.
Results: The average pain score during insertion was 3.2±0.5, and the occurrence of pain was associated with a history of dysmenorrhea (p=0.04) and difficulty during device insertion (p=0.05). There was no difference between pain scores and disability types (p=0.7). Hemoglobin, iron, and ferritin concentrations increased over the course of Kyleena use, with a statistically significant difference for hemoglobin (p=0.02). After one year of use, lean mass increased from 40.9±5.5 kg to 41.8±6.6 kg (p=0.04). Bone mineral density increased from 1.25±0.1 to 1.26±0.2 (p=0.46). Isokinetic evaluation showed an increase in peak torque during dominant limb flexion (p=0.3), and a decrease in peak torque during extension (p=0.7). For total work, the increase occurred in the fourth month of Kyleena IUD use, both for flexion (p=0.3) and extension (p=0.3). There was an increase in vertical jump performance at the fourth and eighth months of Kyleena IUD use (p=0.9), but a decline after one year of use (p=0.3). Regarding the sprint test, there was improvement in time at each four-month interval, and after one year of use, the time decreased from 7.44 seconds to 7.22 seconds (p=0.6). Menstrual bleeding patterns were classified as favorable, and all athletes were highly satisfied with the method.
Conclusion: The Kyleena IUD had a positive effect on the sports performance parameters of Paralympic athletes. After one year of use, the menstrual bleeding pattern was considered favorable, and the athletes were highly satisfied with the method.