title: Time to take human embryo culture seriously.
abstract: Is it important that end-users know the composition of human embryo culture media?
  
  
  
  We argue that there is as strong case for full transparency concerning the composition of embryo culture media intended for human use.
  
  
  
  Published data suggest that the composition of embryo culture media may influence the phenotype of the offspring.
  
  
  
  A review of the literature was carried out.
  
  
  
  Data concerning the potential effects on embryo development of culture media were assessed and recommendations for users made.
  
  
  
  The safety of ART procedures, especially with respect to the health of the offspring, is of major importance. There are reports from the literature indicating a possible effect of culture conditions, including culture media, on embryo and fetal development. Since the introduction of commercially available culture media, there has been a rapid development of different formulations, often not fully documented, disclosed or justified. There is now evidence that the environment the early embryo is exposed to can cause reprogramming of embryonic growth leading to alterations in fetal growth trajectory, birthweight, childhood growth and long-term disease including Type II diabetes and cardiovascular problems. The mechanism for this is likely to be epigenetic changes during the preimplantation period of development. In the present paper the ESHRE working group on culture media summarizes the present knowledge of potential effects on embryo development related to culture media, and makes recommendations.
  
  
  
  There is still a need for large prospective randomized trials to further elucidate the link between the composition of embryo culture media used and the phenotype of the offspring. We do not presently know if the phenotypic changes induced by in vitro embryo culture represent a problem for long-term health of the offspring.
  
  
  
  Published data indicate that there is a strong case for demanding full transparency concerning the compositions of and the scientific rationale behind the composition of embryo culture media.
  
  
  
  This work was funded by The European Society for Human Reproduction and Embryology. No competing interests to declare.
authors.affiliation: Department of Obstetrics and Gynaecology, St. Olav's University Hospital in Trondheim, Trondheim, Norway trondheimivf@gmail.com.
authors.forename: Arne
authors.initials: A
authors.lastname: Sunde
authors.affiliation: Department of Reproductive Medicine, St Mary's Hospital, Central Manchester NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Brison
authors.affiliation: Department of Obstetrics and Gynaecology, IVF Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: John
authors.initials: J
authors.lastname: Dumoulin
authors.affiliation: Embryology, IVF and reproductive genetics group, Institute for Women's Health, University College London, London, UK.
authors.forename: Joyce
authors.initials: J
authors.lastname: Harper
authors.affiliation: Reproductive Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
authors.forename: Kersti
authors.initials: K
authors.lastname: Lundin
authors.affiliation: SISMER, Reproductive Medicine Unit, Bologna, Italy.
authors.forename: M Cristina
authors.initials: MC
authors.lastname: Magli
authors.affiliation: Reproductive Medicine, Gent University Hospital, Gent, Belgium.
authors.forename: Etienne
authors.initials: E
authors.lastname: Van den Abbeel
authors.affiliation: Reproductive Medicine Service, Hospital Universitari Dexeus, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Veiga
mesh_terms: D003470:Culture Media; D046149:Embryo Culture Techniques / Q000379:methods*; D047108:Embryonic Development / Q000502:physiology*; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D027724:Reproductive Techniques, Assisted
chemical_list: D003470:Culture Media
keywords: European Society of Human Reproduction and Embryology; assisted reproductive technology; culture media; effect of in vitro culture on human embryos; regulation of culture media; transparency regarding composition of culture media