title: A pilot trial of large versus small diameter needles for oocyte retrieval.
abstract: BACKGROUND
  This study was designed to determine whether small diameter needles for oocyte retrieval alter oocyte yields in patients undergoing IVF in comparison to standard large diameter needles.
  
  
  METHODS
  We conducted a prospective pilot study of 21 consecutive favorable prognosis patients. In each patient one ovary was randomly allocated to retrieval with either a 20 G/ 35 mm (thin) or 17 G/ 35 mm (standard) needle, the other ovary was then retrieved with the opposite needle.
  
  
  RESULTS
  The standard diameter needle was used to collect a total of 215 oocytes from 355 aspirated follicles (60.6%) compared to 203 oocytes from 352 aspirated follicles (57.7%) with the thinner needle (p = 0.23). Stratifying outcomes by anti-Müllerian hormone (AMH), as indicator of ovarian reserve, and by body mass index (BMI) the oocyte yields, still, did not differ (AMH, r (17) = -0.20, p = 0.44; BMI, r (17) =0.02, p = 0.96). Outcomes also did not vary among women with diminished ovarian reserve (p = 0.17) and in women with normal ovarian reserve (p = 1.00). Operating time was, however, significantly increased by 3.3 minutes per ovary (z = -3.08, p = 0.002) with the thinner needle.
  
  
  CONCLUSIONS
  Needle diameter does not affect oocyte yield, including in obese patients and patients with diminished ovarian reserve. Thinner needles appear to significantly prolong operating time.
authors.affiliation: Center for Human Reproduction, 21 East 69th Street, New York, NY 10021, USA. vkushnir@thechr.com
authors.forename: Vitaly A
authors.initials: VA
authors.lastname: Kushnir
authors.forename: Ann
authors.initials: A
authors.lastname: Kim
authors.forename: Norbert
authors.initials: N
authors.lastname: Gleicher
authors.forename: David H
authors.initials: DH
authors.lastname: Barad
mesh_terms: D000328:Adult; D054304:Anti-Mullerian Hormone / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D006801:Humans; D009339:Needles; D054315:Oocyte Retrieval / Q000295:instrumentation* / Q000379:methods*; D006080:Ovarian Follicle / Q000166:cytology / Q000378:metabolism; D010053:Ovary / Q000166:cytology* / Q000378:metabolism; D010865:Pilot Projects; D011446:Prospective Studies; D013997:Time Factors; D055815:Young Adult
chemical_list: D054304:Anti-Mullerian Hormone; D005640:Follicle Stimulating Hormone