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Category Biochemistry
Test background

Testosterone is primarily synthesised in the testes and, to a lesser extent, the adrenal cortex and ovaries (females). Diminished concentrations may correspond to erectile dysfunction and infertility (males) whereas raised levels may indicate the presence of a testosterone-secreting tumour or, following administration of exogenous steroids (males or females), precocious puberty (males) or polycystic ovary syndrome (PCOS) (females).

Clinical Indications

Diagnosis of fertility and erectile dysfunction Diagnosis of PCOS Monitoring of steroid replacement therapy/detection of steroid misuse Monitoring androgen ablation therapy during treatment for prostatic carcinoma

Reference range


Male 10-30 nmol/L
Female ≤ 2.0 nmol/L
Children <10 years see report
Sample & container required Serum (gold or red top)
Sample volume 0.5 mL
Transport storage For referred samples:
Stable at 2-8°C for 72 hours.
Please freeze pending dispatch for analysis.
Sample can be sent by first class post.
Turnaround time 1 day (samples reflexed for confirmation by LC-MS/MS analysis may take up to 1 week)

Testosterone: SHBG ratio female reference range 1.0-6.0.

NB. From 1st December 2014, the method for female testosterone analysis changed to immunoassay. Samples with elevated results on the immunoassay method will be automatically reflexed for confirmation by LC-MS/MS analysis.

Samples received from external laboratories will continue to be analysed by LC-MS/MS first line; please request TesX to ensure the correct test is requested at booking in.

Grossly haemolysed samples are unsuitable for this assay.