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Macroprolactin (Big-Big Prolactin) Unit Converter
Macroprolactin is an inactive complex formed when the naturally occurring Prolactin hormone binds to Immunoglobulin G (IgG) autoantibodies. Because this large complex (Big-Big Prolactin) is cleared slowly by the body, its presence can cause a falsely elevated Total Prolactin result in standard lab assays.
Clinically, measuring Macroprolactin is essential in diagnosing pseudo-hyperprolactinemia—a condition where the patient has high Total Prolactin but is asymptomatic (since Macroprolactin is biologically inactive). Diagnosis relies on specialized precipitation tests (e.g., PEG precipitation). This converter uses the standard Prolactin conversion factors for reference.
Mass / Molar Units
RecommendedNanograms per milliliter or Picomoles per liter.
Activity Equivalents
Clinical Context
Diagnostic Threshold: Macroprolactin is confirmed when the concentration of the large IgG complex accounts for > 60% of the Total Prolactin detected in the sample.
This condition should be ruled out when a patient has sustained hyperprolactinemia (> 100 ng/mL) but lacks the classic symptoms (galactorrhea, amenorrhea, infertility). The conversion factors below are based on the standard Prolactin monomer: 1 ng/mL ≈ 43.48 pmol/L and 1 ng/mL ≈ 20 µIU/mL (highly assay-dependent).
Clinical References
How to Use This Calculator
Follow these steps to get accurate clinical conversions instantly.
Enter Values
Input the Macroprolactin concentration (either Total or the post-PEG value) into the corresponding unit field (e.g., ng/mL).
Automatic Conversion
The calculator works in real-time, converting between mass, molar, and activity units using standard clinical approximations.
Verify Units
Check the SI Units section. ng/mL is numerically identical to µg/L.
Reset
Use the Clear button to reset all fields before starting a new calculation.
Frequently Asked Questions & Tips
Yes. 1 ng/mL is exactly equal to 1 µg/L.
By measuring Total Prolactin, treating the sample with polyethylene glycol (PEG) to precipitate the large Macroprolactin complex, and then remeasuring the remaining active monomer Prolactin.