Choosing a culture medium: making informed choices

Abstract

To the Editor: We read the paper of Biggers and Summers (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar) and followed the never-ending scientific discussion (or should we say, dispute) on the optimal composition of culture media (2Biggers J.D. McGinnis L.K. Lawitts J.A. One-step versus two-step culture of mouse preimplantation embryos: is there a difference?.Hum Reprod. 2005; 20: 3376-3384Crossref PubMed Scopus (62) Google Scholar, 3Gardner D.K. Lane M. One-step versus two-step culture of mouse preimplantation embryos.Hum Reprod. 2006; 21: 1935-1936Crossref PubMed Scopus (5) Google Scholar) with interest. Critically analyzing the debate (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar, 2Biggers J.D. McGinnis L.K. Lawitts J.A. One-step versus two-step culture of mouse preimplantation embryos: is there a difference?.Hum Reprod. 2005; 20: 3376-3384Crossref PubMed Scopus (62) Google Scholar, 3Gardner D.K. Lane M. One-step versus two-step culture of mouse preimplantation embryos.Hum Reprod. 2006; 21: 1935-1936Crossref PubMed Scopus (5) Google Scholar), the reader cannot help but think that the path of objective discussion has been left and that the argument got personal. Undoubtedly, both authors have provided substantial contributions to the composition of culture media; however, discussion should be objective and factual. Although we regularly use global media and our experience is more in line with Biggers et al. (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar, 2Biggers J.D. McGinnis L.K. Lawitts J.A. One-step versus two-step culture of mouse preimplantation embryos: is there a difference?.Hum Reprod. 2005; 20: 3376-3384Crossref PubMed Scopus (62) Google Scholar), we would like to point out some flaws in their report (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar). To begin with, the statement that “all but one commercially available protocols for the culture of human preimplantation embryos to the blastocyst stage are of the sequential media type” is incorrect. At least one alternative global medium called GM501 (Gynemed, Lensahn, Germany) has been marketed for 5 years and is frequently used in Central Europe and Asia (4Ebert P. Szypajlo B. Tomalak K. Völklein K. Prospective comparison of two commercially available culture media under the provisions of the German embryo protection law.J Turkish-German Gynecol Assoc. 2009; 10: 10-13Google Scholar); hence, Table 1 should be adapted accordingly. Second, it is questionable to argue exclusively on the basis of preliminary data. The abstracts listed in Table 2 had not been peer-reviewed and, thus, are of limited value in this context. Although this limitation was mentioned by the authors (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar) and one paper has been published in the meantime as an original article (5Sepúlveda S. Garcia J. Arriaga E. Diaz J. Noriega-Portella L. Noriega-Hoces L. In vitro development and pregnancy outcomes for human embryos in either a single medium or in a sequential media system.Fertil Steril. 2009; 91: 1765-1770Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar), a strange aftertaste is left since it took these authors (5Sepúlveda S. Garcia J. Arriaga E. Diaz J. Noriega-Portella L. Noriega-Hoces L. In vitro development and pregnancy outcomes for human embryos in either a single medium or in a sequential media system.Fertil Steril. 2009; 91: 1765-1770Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar) almost 3 years to publish their data, which, by the way, are not consistent with the data from the corresponding abstract submitted earlier (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar). It is interesting that some coauthors were deleted from the original list of authors, probably because of conflicting interests. Last, but not least, the authors (1Biggers J.D. Summers M.C. Choosing a culture medium: making informed choices.Fertil Steril. 2008; 90: 473-483Abstract Full Text Full Text PDF PubMed Scopus (110) Google Scholar) mentioned “difficulties in the interpretation of clinical outcomes due to the heterogeneous nature of the IVF patient population”; however, they completely neglected in vitro culture conditions. Different volumes of culture medium and embryo densities within this volume do not allow for comparison of blastulation rates or pregnancy rates. To conclude, we are convinced that both strategies of culturing zygotes up to blastocyst stage have roles in IVF laboratories. In the current situation of competing concepts, parallel usage of both types of media on sibling gametes and embryos is recommended, which would help to reduce dependence on brand names and batch numbers. Choosing a culture medium: making informed choicesFertility and SterilityVol. 90Issue 3PreviewTo analyze critically the reasons justifying the choice of two-step protocols requiring two media for the culture of human preimplantation embryos from the zygote to the blastocyst. Full-Text PDF Reply of the Authors: Choosing a culture medium: making informed choicesFertility and SterilityVol. 93Issue 6PreviewWe thank Ebert and Völklein for drawing our attention to Medium GM501 marketed by Gynemed (Lensahn, Germany). We were not aware at the time of writing our review of any peer-reviewed, journal papers describing the use of Medium GM501 for the extended culture of human preimplantation embryos. The omission of this medium from inclusion in Table 1 is thus understandable, not the flaw that they suggested in their letter. Moreover, the paper by Ebert et al. (1) was published after our review article appeared. Full-Text PDF