title: Evaluation of the one-step eosin-nigrosin staining technique for human sperm vitality assessment.
abstract: BACKGROUND
  The one-step eosin-nigrosin staining technique for assessment of sperm vitality was developed in the 1950s for various mammalian species. Although commonly used on human sperm in semen, a validation for this use has not previously been published.
  
  
  METHODS
  The technique was evaluated on 1235 consecutive semen samples.
  
  
  RESULTS
  The one-step eosin-nigrosin staining technique gave valid results when evaluated with sperm motility data obtained according to World Health Organization standard (1992, 1999). The mean for the sums of stained (i.e. supposedly dead) and motile sperm using the one-step eosin-nigrosin technique was 91% (SD +/- 10%). The distribution of sums for percentage stained and percentage motile sperm was similar, regardless of whether the samples had many or few dead sperm.
  
  
  CONCLUSIONS
  Standardization and quality control of basic semen analysis demands robust, reliable and simple techniques that are easy to learn, and easy to continue to perform in the same way. The one-step eosin-nigrosin technique does not need negative phase contrast optics but can be run with ordinary bright-field microscopy. Since it also includes fewer methodological steps to control, it seems preferable in terms of standardization and quality control management. It should therefore be recommended in the basic semen analysis when sperm vitality is to be assessed.
authors.affiliation: Reproductive Biology and Genetics Group, ACU Birmingham Women's Hospital, Department of Medicine, University of Birmingham, B15 2TG, UK. l.bjorndahl@bham.ac.uk
authors.forename: L
authors.initials: L
authors.lastname: Björndahl
authors.forename: I
authors.initials: I
authors.lastname: Söderlund
authors.forename: U
authors.initials: U
authors.lastname: Kvist
mesh_terms: D000814:Aniline Compounds; D004396:Coloring Agents; D004801:Eosine Yellowish-(YS); D005456:Fluorescent Dyes; D006801:Humans; D008297:Male; D011786:Quality Control; D013081:Sperm Motility; D013194:Staining and Labeling
chemical_list: D000814:Aniline Compounds; D004396:Coloring Agents; D005456:Fluorescent Dyes; C002712:nigrosin; D004801:Eosine Yellowish-(YS)