Controlled studies of the variables involved in culture media for intracytoplasmicsperm injection are needed

Abstract

I read the article published at Fertility and Sterility by Francesco Morgia and collaborators (1Morgia F. Torti M. Montigiani M. Piscitelli C. Giallonardo A. Schimberni M. et al.Use of a medium buffered with N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) in intracytoplasmic sperm injection procedures is detrimental to the outcome of in vitro fertilization.Fertil Steril. 2006; 85: 1415-1419Abstract Full Text Full Text PDF PubMed Scopus (18) Google Scholar) where they said that N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) is detrimental to intracytoplasmic sperm injection (ICSI) procedures. According to these investigators, avoiding HEPES in the medium used for microinjection could improve IVF results. However, they did not specify which polyvinyl pyrrolidone (PVP) they have used in each arm of study (with and without HEPES). It was mentioned “ICSI was performed in all cases according to published procedures” (2Palermo G. Joris H. Devroey P. Van Steirteghem A.C. Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte.Lancet. 1992; 340: 17-18Abstract PubMed Scopus (2875) Google Scholar), but in the cited study the ICSI procedure was done only with HEPES-buffered PVP.I have used HEPES-buffered medium in all steps of gamete manipulation with good results. I agree with the fact that HEPES can modify intracellular pH and harm oocyte fertilization and embryo development, but I believe we can prevent this effect by avoiding PVP injection into oocyte cytoplasm. I read the article published at Fertility and Sterility by Francesco Morgia and collaborators (1Morgia F. Torti M. Montigiani M. Piscitelli C. Giallonardo A. Schimberni M. et al.Use of a medium buffered with N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) in intracytoplasmic sperm injection procedures is detrimental to the outcome of in vitro fertilization.Fertil Steril. 2006; 85: 1415-1419Abstract Full Text Full Text PDF PubMed Scopus (18) Google Scholar) where they said that N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) is detrimental to intracytoplasmic sperm injection (ICSI) procedures. According to these investigators, avoiding HEPES in the medium used for microinjection could improve IVF results. However, they did not specify which polyvinyl pyrrolidone (PVP) they have used in each arm of study (with and without HEPES). It was mentioned “ICSI was performed in all cases according to published procedures” (2Palermo G. Joris H. Devroey P. Van Steirteghem A.C. Pregnancies after intracytoplasmic injection of single spermatozoon into an oocyte.Lancet. 1992; 340: 17-18Abstract PubMed Scopus (2875) Google Scholar), but in the cited study the ICSI procedure was done only with HEPES-buffered PVP. I have used HEPES-buffered medium in all steps of gamete manipulation with good results. I agree with the fact that HEPES can modify intracellular pH and harm oocyte fertilization and embryo development, but I believe we can prevent this effect by avoiding PVP injection into oocyte cytoplasm. Use of a medium buffered with N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) in intracytoplasmic sperm injection procedures is detrimental to the outcome of in vitro fertlizationFertility and SterilityVol. 85Issue 5PreviewThis study was conducted to determine whether N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES)–buffered medium used for the microinjection of sperm into oocytes may be detrimental for the embryo. Full-Text PDF Reply of the authors:Fertility and SterilityVol. 87Issue 2PreviewWe thank Dr. Meyer de Moraes for his interest in our article and for giving us the opportunity to clarify certain issues concerning tcertain issuehe use of N-hydroxyethylpiperazine-N-ethanesulfonate (HEPES) in the medium for intracytoplasmic sperm injection (ICSI) procedure, discussed in our study (1). Full-Text PDF