The resazurin reduction test provides an assessment of sperm activity.

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.