title: The impact of spermatozoa preincubation time and spontaneous acrosome reaction in intracytoplasmic sperm injection: a controlled randomized study.
abstract: OBJECTIVE
  To determine the optimum time interval between semen processing and incubation before intracytoplasmic sperm injection (ICSI) and correlate it with the acrosomal reaction rate.
  
  
  METHODS
  Controlled randomized study.
  
  
  METHODS
  The Egyptian IVF-ET Center.
  
  
  METHODS
  Couples with male factor infertility undergoing ICSI using ejaculated semen.
  
  
  METHODS
  The patients were prospectively randomized according to differences in sperm preincubation time before ICSI into 1-hour, 3-hour, and 5-hour groups. The status of the acrosome was studied using electron microscopy.
  
  
  METHODS
  The primary outcome measures were fertilization rate and acrosome reaction rate. Secondary outcome measures were the implantation and pregnancy rates.
  
  
  RESULTS
  The rate of acrosomally reacted spermatozoa was the highest (68.2%) after 5 hours of incubation and lowest (25.6%) after 1 hour of incubation. The difference was statistically significant. The fertilization rate was the highest (74%) using spermatozoa incubated for 3 hours as compared with 1 hour (70%) and 5 hours (67%), but the difference was not statistically significant.
  
  
  CONCLUSIONS
  Acrosome reaction is time dependent; the optimum incubation time of spermatozoa before ICSI was 3 hours, which resulted in the highest fertilization rate.
authors.affiliation: The Egyptian IVF-ET Center, Cairo, Egypt. ragaaivf@hotmail.com
authors.forename: Ragaa T
authors.initials: RT
authors.lastname: Mansour
authors.forename: Mennatallah G
authors.initials: MG
authors.lastname: Serour
authors.forename: Amal M
authors.initials: AM
authors.lastname: Abbas
authors.forename: Ahmed
authors.initials: A
authors.lastname: Kamal
authors.forename: Nevine A
authors.initials: NA
authors.lastname: Tawab
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Aboulghar
authors.forename: Gamal I
authors.initials: GI
authors.lastname: Serour
mesh_terms: D020101:Acrosome Reaction; D000328:Adult; D004534:Egypt / Q000453:epidemiology; D005260:Female; D006801:Humans; D007248:Infertility, Male / Q000453:epidemiology* / Q000628:therapy*; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D012662:Semen Preservation / Q000379:methods* / Q000706:statistics & numerical data*; D020554:Sperm Injections, Intracytoplasmic / Q000706:statistics & numerical data*; D013997:Time Factors; D016896:Treatment Outcome