Serum Androgen Profile of Elite Athletes

The binary sex classification protects elite female athletes from the male physical advantages arising from puberty; however, mutations causing XY Disorders of Sex Development (DSD) challenge the binary sex classification. Hormonal features of the most frequent XY DSDs in sports, androgen insensitivity syndrome [AIS] and 5α-reductase type 2 deficiency [5ARD] are not well described.

To define serum androgen profiles in elite Athletics (Track and Field) events.

Serum samples from elite athletes (n=1689; male 889, female 800; n=5516 samples, median 3 per person) were analysed by LCMS for serum testosterone [T], dihydrotestosterone [DHT] and androstenedione in 19 WADA-accredited laboratories. Serum steroids and ratios were analyzed by linear mixed model for repeated measures with adjustment for multiple comparisons and imputation for left-censored (DHT) data. Among females, XY DSD identified by adult male serum T concentrations, had clinical diagnosis of 5ARD, AIS or unclassified (UNCL].

XY DSD comprised 12 with 5ARD with two with AIS (1 complete). Excluding pregnancy or androgen doping samples, men had higher serum T (n=2671, 19.7 ± 0.1 nmol/L) and T/DHT ratio (n=1903, 14.4 ± 0.2) than women (n=2793, 1.1 ± 0.1 nmol/L; n=1809, 3.7 ± 0.12, respectively) with XY DSD featuring male-like results (n=52, 28.9 ± 0.8 nmol/L; n=39; 32.0 ± 1.3).

The prevalence of XY DSD in elite female athletes greatly exceeds that of the community with a high proportion androgen sensitive 5ARD. Serum T/DHT ratio by LCMS to characterize 5ARD can be extended to elite athletes.