The haematological module of the athlete biological passport (ABP) monitors longitudinal haematological variations that could be indicative of blood manipulation. This study applied a multi-parametric model previously validated in elite cyclists to compare inferred and actual PV variations, whereas the potential influence of the oral contraceptive pill (OCP) cycle on the ABP blood biomarkers and plasma volume (PV) in 14 physically active women taking OCPs was also investigated. Blood and serum samples were collected each week for 8 weeks, and the ABP haematological variables were determined according to the World Anti-Doping Agency guidelines.Transferrin (sTFN), ferritin (FERR), albumin (ALB), calcium (Ca), creatinine (CRE), total protein (TP) and low-density lipoprotein (LDL) were additionally computed as 'volume-sensitive' variables in a multivariate analysis to determine individual estimations of PV variations. Actual PV variations were indirectly measured using a validated carbon monoxide rebreathing method. We hypothesised ABP markers to be stable during a standard OCP cycle and estimated PV variations similar to measured PV variations. Measured PV variations were in good agreement with the predictions and allowed to explain an atypical passport finding (ATPF). The ABP biomarkers, Hbmass and PV were stable over 8 weeks. Significant differences occurred only between Week 7 and Week 1, with lower levels of haemoglobin concentration ([Hb]), haematocrit (HCT) and red blood cell count (RBC)(À4.4%, p < 0.01; À5.1%, p < 0.01; À5.2%, p < 0.01) and higher levels of PV at week 7 (+9%, p = 0.05). We thus concluded that estimating PV variations may help interpret individual ABP haematological profiles in women.

The steroidal module of the athlete biological passport (ABP) targets the use of pseudo‐endogenous androgenous anabolic steroids in elite sport by monitoring urinary steroid profiles. Urine and blood samples were collected weekly during two consecutive oral contraceptive pill (OCP) cycles in 15 physically active women to investigate the low urinary steroid concentrations and putative confounding effect of OCP. In urine, testosterone (T) and epitestosterone (E) were below the limit of quantification of 1 ng/ml in 62% of the samples. Biomarkers' variability ranged between 31% and 41%, with a significantly lesser variability for ratios (except for T/E [41%]): 20% for androsterone/etiocholanolone (p < 0.001) and 25% for 5α‐androstane‐3α,17β‐diol/5ß‐androstane‐3α,17β‐diol (p < 0.001). In serum, markers' variability (testosterone: 24%, androstenedione: 23%, dihydrotestosterone: 19%, and T/A4: 16%) was significantly lower than in urine (p < 0.001). Urinary A/Etio increased by >18% after the first 2 weeks (p < 0.05) following withdrawal blood loss. In contrast, serum T (0.98 nmol/l during the first week) and T/A4 (0.34 the first week) decreased significantly by more than 25% and 17% (p < 0.05), respectively, in the following weeks. Our results outline steroidal variations during the OCP cycle, highlighting exogenous hormonal preparations as confounder for steroid concentrations in blood. Low steroid levels in urine samples have a clear negative impact on the subsequent interpretation of steroid profile of the ABP. With a greater analytical sensitivity and lesser variability for steroids in healthy active women, serum represents a complementary matrix to urine in the ABP steroidal module.

The steroidal module of the Athlete Biological Passport (ABP) targets the use of exogenous androgenous anabolic steroids (EAAS) in elite sport by monitoring urinary steroid profiles. Urine and blood samples were collected weekly during two consecutive OCP cycles (8 weeks) in 15 physically active women to investigate the low urinary steroid concentrations and putative confounding effect of OCP. In urine, testosterone (T) and/or epitestosterone (E) were below the limit of quantification of 1 ng/mL in 62% of the samples. Biomarkers' variability ranged between 31% and 41%, with a significantly lesser variability for ratios (except for T/E (41%)): 20% for androsterone/etiocholanolone (p < 0.001) and 25% for 5alpha-androstane-3lapha,17beta-diol/5beta-androstane-3,17beta-diol (p < 0.001). In serum, markers variability (testosterone: 24%, androstenedione: 23%, dihydrotestosterone: 19% and T/A4: 16%) was significantly lower than in urine (p < 0.001). Urinary A/Etio increased by > 18% after the first two weeks (p < 0.05) following blood loss. In contrast, serum T (0.98 nmol/L during the first week), and T/A4 (0.34 the first week) decreased significantly by more than 25% and 17% (p < 0.05), respectively in the following weeks. Our results outline steroidal variations during the OCP cycle, highlighting exogenous hormonal preparations as confounder for steroid concentrations in blood. Low steroid levels in urine samples have a clear detrimental impact on the subsequent interpretation of steroidal variations for the ABP. With a greater analytical sensitivity and lesser variability for steroids in healthy active women, serum represents a complementary matrix to urine in the ABP steroidal module.

Anemia is a widespread disease commonly diagnosed through hemoglobin concentration ([Hb]) thresholds set by the World Health Organization (WHO). However, [Hb] is subject to significant variations mainly due to shifts in plasma volume (PV) which impair the diagnosis of anemia and other medical conditions. The aim of this study was to develop a model able to accurately predict total hemoglobin mass (Hbmass) and PV based on anthropometric and complete blood count (CBC) analyses. 769 CBC coupled to measures of Hbmass and PV using the CO-rebreathing method were used with a machine learning tool in a numeric computing platform (MATLAB regression learner app) to calculate the model. For the predicted values, root mean square error (RMSE) was of 37.9 g and 50.0 g for Hbmass, and 194 ml and 268 ml for PV, in women and men, respectively. Measured and predicted data were significantly correlated (p<0.001) with the coefficient of determination (R2) ranging from 0.73 to 0.81 for Hbmass, and PV, in both women and men. The bland-altman bias between estimated and measured variables was in average of -0.69 for Hbmass and 0.73 for PV. This study proposes a valid model with a high prediction potential for Hbmass and PV, providing relevant complementary data in numerous contexts. This method can notably bring information applicable to the epidemiology of anemia, particularly in countries with high prevalence or in specific population such as high-altitude communities.