title: Predictive value of the number of oocytes retrieved at ultrasound-directed follicular aspiration with regard to fertilization rates and pregnancy outcome in intracytoplasmic sperm injection treatment cycles.
abstract: OBJECTIVE
  To determine the number of oocytes sufficient for satisfactory fertilization and pregnancy rates in intracytoplasmic sperm injection cycles.
  
  
  METHODS
  A retrospective analysis.
  
  
  METHODS
  A private assisted conception unit.
  
  
  METHODS
  Women in whom at least one oocyte was retrieved in consecutive ultrasound-directed follicular aspirations between June 1999 and June 2001.
  
  
  METHODS
  Standard protocol for pituitary down-regulation and ovarian stimulation.
  
  
  METHODS
  Number of oocytes retrieved, embryos transferred, fertilization, and pregnancy rates.
  
  
  RESULTS
  The numbers of oocytes obtained per cycle were classified into groups A, B, C, and D, consisting of 110, 124, 96, and 122 cycles, with 1-5, 6-10, 11-15, >15 oocytes retrieved from each patient in each group, respectively. The chance of not obtaining a viable oocyte for injection was highest in group A (5.5%). Most fertilization failures occurred in group A (11.8%). Total cleavage failure occurred in the greatest percentage of cycles in group A (3.6%) with a significantly lower mean number of embryos (1.9 +/- 1.7) being transferred. The clinical pregnancy rate was also lowest in group A (7.1%) compared with groups B (25.8%), C (20.8%), and D (23.8%).
  
  
  CONCLUSIONS
  Retrieval of between 6 and 10 oocytes per patient and transfer of a maximum of three cleavage-stage embryos results in high pregnancy rates.
authors.affiliation: Assisted Conception Unit, The Bridge Clinic, Ltd., Victoria Island, Lagos, Nigeria.
authors.forename: Nwora A
authors.initials: NA
authors.lastname: Melie
authors.forename: Olutope A
authors.initials: OA
authors.lastname: Adeniyi
authors.forename: Osaro M
authors.initials: OM
authors.lastname: Igbineweka
authors.forename: Richard A
authors.initials: RA
authors.lastname: Ajayi
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use; D006801:Humans; D009865:Oocytes / Q000166:cytology*; D006080:Ovarian Follicle / Q000166:cytology*; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic
chemical_list: D005300:Fertility Agents, Female