Detection of testosterone microdosing in healthy females

Abstract

The ready detectability of synthetic androgens by mass spectrometry (MS)-based antidoping tests has reoriented androgen doping to using testosterone (T), which must be distinguished from its endogenous counterpart making detection of exogenous T harder. We investigated urine and serum steroid and hematological profiling individually and combined to determine the optimal detection model for T administration in women. Twelve healthy females provided six paired blood and urine samples over 2 weeks prior to treatment consisting of 12.5-mg T in a topical transdermal gel applied daily for 7 days. Paired blood and urine samples were then obtained at the end of treatment and Days 1, 2, 4, 7, and 14 days later. Compliance with treatment and sampling was high, and no adverse effects were reported. T treatment significantly increased serum and urine T, serum dihydrotestosterone (DHT), urine 5α-androstane-3α,17β-diol (5α-diol) epitestosterone (E), and urine T/E ratio with a brief window of detection (2-4 days) as well as total and immature (medium and high fluorescence) reticulocytes that remained elevated over the full 14 posttreatment days. Carbon isotope ratio MS and the OFF score and Abnormal Blood Profile score (ABPS) were not discriminatory. The optimal multivariate model to identify T exposure combined serum T, urine T/E ratio with three hematological variables (% high fluorescence reticulocytes, mean corpuscular hemoglobin, and volume) with the five variables providing 93% correct classification (4% false positive, 10% false negatives). Hence, combining select serum and urine steroid MS variables with reticulocyte measures can achieve a high but imperfect detection of T administration to healthy females.

Supra‐physiological doses of anabolic androgenic steroids impact erythropoietin and blood parameters

“…29 Here we noted that all RET fractions, that is, RET%, IRF, and HFR, were higher in individuals with ASIH and to some degree correlated to the androgen load. The result is in line with a previous study where administration of T increased HFR, suggesting that HFR may function as a supplementary marker for T detection in women, together with serum T. 19 Considering that androgens interact with ABP biomarkers it would be of interest to study ABP after co-administration of T and rEPO, but to our knowledge no such study has been performed in healthy subjects. This of particular interest since among elite athletes, a co-use of EPO and AAS has been reported, and they prefer to use low doses of T and ESAs (micro-dosing) to avoid testing positive in doping control tests.…”

“…[16][17][18] Consequently, RET% has been suggested to function as a marker for T intake and there is an interest to further understand how the blood parameters and androgens are interacting for improved interpretation of the hematological and endocrine modules of the ABP. A recent study indicates that high fluorescence reticulocyte fraction (HFR) was sensitive to T intake in women, 19 but the HFR association to supra-physiological exposure to AAS in men has not been studied. It is possible that supra-phycological doses of AAS exert different effects on the reticulocyte fractions.…”

Annual banned‐substance review—Analytical approaches in human sports drug testing 2021/2022–

“…This approach, however, has been particularly challenging in female subjects, especially when microdosed transdermally. Hence, in a controlled study with 12 healthy females, Savkovic et al assessed the utility of combining ABP information from both urine and blood as well as serum steroid profile data 27 . Testosterone (12.5 mg) was transdermally applied once per day over a period of 1 week, and paired blood and urine samples were collected prior to and up to 14 days after the end of the treatment.…”