title: Mechanical agitation during the in vitro culture of human pre-implantation embryos drastically increases the pregnancy rate.
abstract: BACKGROUND
  The in vivo developing embryo is naturally exposed to constant vibrations of around 6 Hz, increasing to 20 Hz when the oviductal fluid is mechanically agitated by the cilia. This study examines the effects on viability of subjecting human pronuclear oocytes and embryos to mechanical agitation during their in vitro culture before transplantation.
  
  
  METHODS
  Metaphase-II oocytes were ICSI/IVF with morphologically normal spermatozoa and then divided into two groups according to whether the cells underwent mechanical agitation (20 Hz over 5 seconds once per hour) of the culture medium (Group 2, n=23) or were cultured without mechanical agitation (Group 1, n=23). The fertilization rate of oocytes was recorded 18 hours later. Embryo development was monitored every day during the whole period of in vitro culture up to the embryo transfer on day 3, 4 or 5.
  
  
  RESULTS
  Pregnancy rates after the transfer of 3 Day embryos in Group 1 and Group 2 were 50% and 80%, and of 5 Day embryos in Group 1 and Group 2 were 36% and 73%, respectively.
  
  
  CONCLUSIONS
  The in vitro culture of human embryos in a medium subjected to regular short bursts of mechanical agitation drastically increases their development rate.
authors.affiliation: Section of Gynaecological Endocrinology and Reproductive Medicine, University of Ulm, Germany. e.isachenko@yahoo.de
authors.forename: Evgenia
authors.initials: E
authors.lastname: Isachenko
authors.forename: Robert
authors.initials: R
authors.lastname: Maettner
authors.forename: Vladimir
authors.initials: V
authors.lastname: Isachenko
authors.forename: Steffen
authors.initials: S
authors.lastname: Roth
authors.forename: Rolf
authors.initials: R
authors.lastname: Kreienberg
authors.forename: Karl
authors.initials: K
authors.lastname: Sterzik
mesh_terms: D001755:Blastocyst / Q000502:physiology*; D018929:Cell Culture Techniques / Q000379:methods*; D002470:Cell Survival / Q000502:physiology; D016009:Chi-Square Distribution; D004624:Embryo Transfer; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008297:Male; D011247:Pregnancy; D020554:Sperm Injections, Intracytoplasmic; D014732:Vibration