D-Dimer
Definition
A fibrin degradation product generated when cross-linked fibrin is cleaved by plasmin. Elevated D-dimer in menstrual blood reflects the active fibrinolytic process; clinical D-dimer assays have been adapted for forensic stain analysis.
- Origin
- Cleavage of cross-linked fibrin by plasmin
- Type
- Fibrin degradation product
- Forensic use
- Marker for identifying menstrual blood stains
- Assay origin
- Adapted from clinical D-dimer diagnostic tests
Common questions
Why does D-dimer help separate menstrual blood from peripheral blood stains?+
Menstrual blood undergoes active local fibrinolysis in the uterus before shedding, so it carries elevated D-dimer relative to venous or capillary blood, which has intact clotting and only produces D-dimer once a clot forms and is broken down. Elevated levels in a stain therefore support, though do not alone confirm, a menstrual origin.
What are the limits of using D-dimer as a stand-alone marker for menstrual blood?+
D-dimer alone is not specific to menstrual blood since any degrading clot, including from a wound, will eventually generate it, so forensic protocols typically combine D-dimer with other markers such as hemoglobin variants or mRNA profiling for a reliable body-fluid determination rather than relying on D-dimer in isolation.
Related terms
- Endometrial Shedding
- The physiological process by which the functional layer of the uterine endometrium is broken down and expelled during menstruation. The shedding process...
- Fibrinolysis
- The enzymatic breakdown of fibrin by plasmin, which is generated from plasminogen by tissue plasminogen activator (tPA). Menstrual blood has high tPA...
- Matrix Metalloprotease 10 (MMP-10)
- An endopeptidase of the MMP family involved in extracellular matrix remodelling during endometrial breakdown and shedding. Significantly elevated in menstrual blood and...
- mRNA Profiling
- Detection of messenger RNA transcripts specific to particular tissues or body fluids. Endometrial-specific transcripts (LEFTY2, MMP-10 mRNA, others) can distinguish menstrual blood...
- Tissue Plasminogen Activator (tPA)
- A serine protease secreted by endometrial cells and vascular endothelium that converts plasminogen to plasmin. Elevated in menstrual blood relative to peripheral...