title: Spontaneously developed tail swellings (SDTS) influence the accuracy of the hypo-osmotic swelling test (HOS-test) in determining membrane integrity and viability of human spermatozoa.
abstract: OBJECTIVE
  To investigate the prevalence of spontaneously developed tail swellings (SDTS) in human sperm samples that are commonly encountered in the laboratory, and their influence on the hypo-osmotic swelling test (HOS-test).
  
  
  METHODS
  Ejaculated, epididymal, and testicular sperm were evaluated for SDTS. Further, HOS-test scores were compared with those of vital stains using column washed sperm maintained in the laboratory.
  
  
  RESULTS
  SDTS, at <10%, was present in all types of sperm samples. The highest and lowest occurrences of SDTS were found in cryopreserved sperm, and column-washed sperm respectively. SDTS can inflate the HOS-test score, and so lower the accuracy of the HOS-test. However, the HOS-test efficiency can be improved by assessing SDTS in the sample.
  
  
  CONCLUSIONS
  HOS-test and vital stain cannot be used interchangeably in all circumstances for sperm viability determination. The accuracy of the HOS-test can be enhanced by incorporating SDTS as a correction factor.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA. amhossai@utmb.edu
authors.forename: Amjad
authors.initials: A
authors.lastname: Hossain
authors.forename: Collin
authors.initials: C
authors.lastname: Osuamkpe
authors.forename: Shaikat
authors.initials: S
authors.lastname: Hossain
authors.forename: John Y
authors.initials: JY
authors.lastname: Phelps
mesh_terms: D000328:Adult; D002463:Cell Membrane Permeability / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation; D006801:Humans; D007038:Hypotonic Solutions / Q000494:pharmacology; D008297:Male; D009997:Osmotic Pressure; D055101:Semen Analysis / Q000379:methods*; D012662:Semen Preservation; D013081:Sperm Motility / Q000187:drug effects; D053625:Sperm Retrieval; D013082:Sperm Tail / Q000648:ultrastructure*; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology
chemical_list: D007038:Hypotonic Solutions