Test Background CBG is the major binding protein for cortisol, with a smaller amount bound to albumin, and transports cortisol in the blood in an inactive form. Elevated CBG levels are seen in pregnancy and on oral contraceptive or oestrogen treatment. Low CBG levels may be observed in hyperinsulinaemic states, nephotic syndrome and chronic liver disease.
Interpretation of dynamic function tests of the HPA axis Investigation of abnormal unexplained cortisol concentrations.
Adult male 27.1-52.3 mg/L Adult female 31.0-53.4 mg/L