Determination of urinary norandrosterone excretion in females during one menstrual cycle by gas chromatography/mass spectrometry

Abstract

Conjugated norandrosterone is the main urinary metabolite of anabolic steroids like nandrolone, norandrostenedione and norandrostenediol. Nandrolone traces of endogenous origin have been identified in human follicular fluid, and further investigations revealed urinary excretion of norandrosterone in pregnant and non-pregnant females and even males. A threshold level for the norandrosterone concentration in urine has been established when controlling the administration of prohibited nandrolone or its precursors in human doping control. This level has been set to 2 ng/mL for males and females. To investigate the excretion of conjugated norandrosterone in females more systematically, we collected daily urine samples from 12 female volunteers during a whole menstrual cycle. These samples were analysed for norandrosterone down to a limit of quantification and identification of 0.05 ng/mL (180 pmol/L). The results clearly show that all the volunteers excreted norandrosterone glucuronide in a characteristic pattern during one menstrual cycle. Concentrations in urine were considerably lower at the beginning of the follicular and the end of the luteal phases than midcyclic. Peak concentrations up to 0.8 ng/mL (2.9 nmol/L) were recorded and they were three to four times higher than the values at the beginning and end of the cycle. The time of the peak concentration was clearly related to the increased excretion of luteinizing hormone. These results strongly support the possibility of endogenous nandrolone production as a side reaction to enzymatic aromatisation. However, a threshold value of 2 ng/mL for reporting adversed findings in doping control of females was never reached in any of the samples.

Quantification and Profiling of 19-Norandrosterone and 19-Noretiocholanolone in Human Urine after Consumption of a Nutritional Supplement and Norsteroids

“…Recent studies have shown that 19-NA is also the main urinary metabolite produced by the administration of 19-norsteroids (15) and in the urine of pregnant women (11). Other studies have reported that the administration of OTC nutritional supplements containing 19-norandrostenedione could also result in positive urine test results for the nandrolone metabolite, 19-NA (19-22).…”

“…Exercise has been shown to affect the urinary excretion of nandrolone metabolites (13,14). Furthermore, 19-NA was found to be the main urinary metabolite of norandrostenedione and norandrostenediol and a minor metabolite of oral contraceptives such as norethisterone (15). Oral administration of nandrolone and other 19-norsteroids was primarily excreted to 19-NA, 19-NE, and norepiandrosterone, the latter found exclusively as its sulfoconjugate while the first two are predominantly excreted as glucuronide derivatives (16).…”

Carbon isotope ratios of nandrolone, boldenone, and testosterone preparations seized in Norway compared to those of endogenously produced steroids in a Nordic reference population

“…[12] In addition, small amounts of 19-norandrosterone may be present in female urine, in general. [13,14] The possible endogenous production of nandrolone and boldenone represents a complicating issue in doping control. Different approaches to differentiating between natural production and exogenous administration of boldenone [15] and nandrolone [16,17] preparations have been proposed, but the application of gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) remains the most promising.…”

“…Different approaches to differentiating between natural production and exogenous administration of boldenone [15] and nandrolone [16,17] preparations have been proposed, but the application of gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) remains the most promising. [8,[18][19][20][21][22][23] The 13 C/ 12 C isotope ratios, measured by this technique are expressed as δ 13 C VPDB , relative to an international standard Vienna Pee Dee Belemnite (VPDB) limestone. [24] While endogenously produced steroids reflect the 13 C/ 12 C isotope ratio of the person's diet followed by the steroid biosynthesis, steroid preparations are characterized through their raw materials for anabolic-androgenic steroid synthesis.…”

“…C VPDB values of seized boldenone and nandrolone preparations to decide if the steroids themselves were depleted in 13 C, compared to what is normally seen in endogenously produced steroids. In addition, several testosterone preparations were analyzed.…”