Specimen Requirements

Container/Tube Type: 

Green No Gel (Lithium Heparin)
Light Green (Heparin Plasma Separator Tube)
Red (No Additive)
SST (Serum Separator)

Preferred Collection Container: 

Green No Gel (Lithium Heparin)
Light Green (Heparin Plasma Separator Tube)

Also Acceptable Collection Container: 

Plasma from Lavender tubes is acceptable but will not route in the Laboratory Information System (Sunquest).

Transport Information: 

3.0 mL blood/1.0 mL serum

Minimum Sample Volume:

1.0 mL blood/0.3 mL serum

Remarks: 

Serum concentrations of testosterone in both sexes during the first week of life average about 25 ng/dL. In male infants, values increase sharply in the second week to maximum (mean about 175 ng/dL) at about 2 months, which lasts until about 6 months of age. In female infants, values decrease in the first week and remain low throughout early childhood. Levels increase during puberty to adult values and are related to the pubertal stage rather than chronological age.