title: Prospective randomized comparison of two embryo culture systems: P1 medium by Irvine Scientific and the Cook IVF Medium.
abstract: OBJECTIVE
  To compare the efficacy of two commercially available in vitro fertilization (IVF) and embryo culture media systems: the glucose-free P1 Medium supplemented with 20% synthetic serum substitute (SSS) (Irvine Scientific), and the Cook IVF Medium (Cook, Australia).
  
  
  METHODS
  A prospective randomized study. Medical center-based IVF Unit affiliated to the Faculty of Medicine of Tel Aviv University. IVF patients were randomly assigned to either P1 Medium supplemented with 20% SSS (182 patients, 196 cycles) or Cook Medium (167 patients, 179 cycles).
  
  
  RESULTS
  Fertilization rates were similar with both media (52.3 +/- 26.1 and 53.8 +/- 27.6, respectively). Likewise, no difference was found in morphological characteristics and grading of cultured embryos. However, a significantly higher proportion of the embryos incubated in the P1 Medium reached the four-cell stage on day 2 or the 6-cell stage on day 3 postfertilization, compared to those incubated in Cook Medium (54.3% vs. 41.9%, p < 0.0001). Clinical pregnancy and delivery rates were improved when oocytes and embryos were cultured in P1 Medium. Finally, Implantation rate was significantly higher in the P1 Medium Group (9.9% vs. 6%, respectively).
  
  
  CONCLUSIONS
  Our results suggest that the P1 Medium may be associated with a higher embryo cleavage rate and improved implantation rates compared to the Cook IVF Medium.
authors.affiliation: The IVF Unit, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. dalitb@tasmc.health.gov.il
authors.forename: Dalit
authors.initials: D
authors.lastname: Ben-Yosef
authors.forename: Ami
authors.initials: A
authors.lastname: Amit
authors.forename: Foad
authors.initials: F
authors.lastname: Azem
authors.forename: Tamar
authors.initials: T
authors.lastname: Schwartz
authors.forename: Tania
authors.initials: T
authors.lastname: Cohen
authors.forename: Nava
authors.initials: N
authors.lastname: Mei-Raz
authors.forename: Ariela
authors.initials: A
authors.lastname: Carmon
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Lessing
authors.forename: Yuval
authors.initials: Y
authors.lastname: Yaron
mesh_terms: D003470:Culture Media / Q000737:chemistry*; D010064:Embryo Implantation; D004622:Embryo, Mammalian / Q000166:cytology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies
chemical_list: D003470:Culture Media