Pathology Handbook



Sex Hormone Binding Globulin

Clinical Indications

SHBG is the major serum testosterone binding protein and binds over 70% of testosterone.

SHBG levels are suppressed by increased androgen levels and elevated by increased oestrogen (e.g. during pregnancy or treatment with some oral contraceptives).

The primary reason for measurement of SHBG is to calculate free androgen status from total tesosterone levels and is useful if total testosterone levels are borderline.

SHBG levels are not helpful in discriminating between groups of patients with suspected androgen excess.

SHBG levels are elevated in thyrotoxicosis and decreased in hypothyroidism and SHBG may be used as a marker of thyroid status in patients with thyroid hormone resistance. 

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Analysed if specific criteria met.

Specific Criteria

Female total testosterone greater than 1.5 nmol/L. Assessment of thyroid status in thyroid hormone resistance. Otherwise if requested by Consultant Endocrinologist or agreed with Consultant Biochemist.

Turnaround Time



Serum in yellow top (SST) tube


2 mL


Vacutainer gold top

Causes for Rejection

Not meeting specific criteria for analysis. 

Unlabelled or inadequately labelled sample.

Reference Range

Males < 49ys: 18-54

Males > 50yrs: 21-77

Females < 49yrs: 32-128

Females > 50yrs: 27-128