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Updated: Aug 16, 2026
Fluorimetric Techniques for the Assessment of Sperm Membranes
Published on: November 28, 2018
The resazurin reduction test provides an assessment of sperm activity
R H Glass1, S A Ericsson, R J Ericsson
1Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California-San Francisco 94123-0132.
Objective:
The objective of the study was to determine if reduction of the dye resazurin by semen could be correlated with the concentration of motile sperm.
Design:
After assessment of sperm count and motility, specimens were incubated for 1 hour with resazurin (25 micrograms/mL of semen) and visual color changes indicative of dye reduction noted.
Setting:
Specimens were obtained from men seeking care for infertility at one of four sites: (1) University of California, San Francisco (UCSF) In Vitro Fertilization Program; (2) UCSF Andrology Laboratory; (3) a gynecological practice in Maine; and (4) a private andrology laboratory in Southern California.
Patients:
Individuals were self-selected by their desire to have a semen analysis in conjunction with the diagnosis or treatment of infertility.
Interventions:
None.
Main Outcome Measure:
The reduction of the dye resazurin and its correlation with motile sperm density.
Results:
When the motile sperm concentration was greater than or equal to 20 X 10(6)/mL, 86% of specimens produced a positive color change. Conversely, 86% of specimens with a motile sperm concentration of less than 20 X 10(6)/mL either did not change color or changed only over a narrow range.
Conclusion:
Reduction of resazurin offers an assessment of the active sperm in a specimen without the need to do a sperm count or evaluation of motility.
