title: Shorter abstinence decreases sperm deoxyribonucleic acid fragmentation in ejaculate.
abstract: OBJECTIVE
  To evaluate the relationship between duration of sexual abstinence and sperm selection on sperm DNA fragmentation (SDF).
  
  
  METHODS
  Prospective study based on normozoospermic individuals.
  
  
  METHODS
  Fertility and IVF unit and university unit for research.
  
  
  METHODS
  Two cohorts of normozoospermic individuals: 21 men (aged 25-35 years) attending a clinic and with clearly adverse female factors; and a group of 12 selected donors (aged 20-25 years).
  
  
  METHODS
  SDF assessment using the sperm chromatin the dispersión test (Halosperm) in two cohorts of normozoospermic men.
  
  
  METHODS
  SDF assessment after 24 hours of abstinence with recurrent ejaculation (one every 24 hours) using neat sperm samples; and SDF assessment before and after sperm selection with abstinence of 3 hours.
  
  
  RESULTS
  Lower baseline levels of SDF were observed after shorter periods of abstinence between ejaculations (24 hours and 3 hours) than those recommended. This effect is much more marked after quick repetitive ejaculation (3 hours of abstinence) and sperm selection.
  
  
  CONCLUSIONS
  The present results challenge the role of abstinence in current male infertility treatments and suggest that SDF can be efficiently reduced by a biological practice consisting of short-term recurrent ejaculation coupled with effective sperm selection.
authors.affiliation: Departamento de Biología, Unidad de Genética, Universidad Autónoma de Madrid, Madrid, Spain. jaime.gosalvez@uam.es
authors.forename: Jaime
authors.initials: J
authors.lastname: Gosálvez
authors.forename: Mercedes
authors.initials: M
authors.lastname: González-Martínez
authors.forename: Carmen
authors.initials: C
authors.lastname: López-Fernández
authors.forename: José L
authors.initials: JL
authors.lastname: Fernández
authors.forename: Pascual
authors.initials: P
authors.lastname: Sánchez-Martín
mesh_terms: D000328:Adult; D053938:DNA Fragmentation; D004542:Ejaculation; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000628:therapy*; D008297:Male; D011446:Prospective Studies; D027724:Reproductive Techniques, Assisted; D055101:Semen Analysis; D012746:Sexual Abstinence; D013030:Spain; D013094:Spermatozoa / Q000473:pathology*; D013997:Time Factors; D055815:Young Adult