{"paper_id":"9dfac49c-6d3a-4ef9-9bc4-8c7cff5f4384","body_text":"Purpose\nMurine two-cell embryos (n =5573) were cultured for 96 hr in human tubal fluid (HTF) medium (n =2709) or alpha modification of minimum essential medium (MEM; n =2864) through the hatched blastocyst stage from mid-1990 to mid-1991. An additional 373 embryos were cultured in MEM or HTF with 0, 1, 5, or 10 ng/ml E. coli endotoxin. A total of 17 patients had supernumerary embryos simultaneously cultured in HTF (n =48) or MEM (n =61). Additionally, pregnancy rates were compared for July to December 1990, when MEM was used as growth medium, and for July to December 1989, when HTF was used.\nResults\nBlastocyst formation was higher (P <0.001) for murine embryos cultured in MEM (blasts = 95%) compared to HTF (blasts = 70%). When cultured with endotoxin, blastocyst formation was higher (P <0.01) for embryos cultured in MEM compared with HTF for controls and at each endotoxin level. No difference in human blastocyst development was observed in HTF and MEM. However, more MEM-cultured blastocysts were cryopreserved (P <0.05). There also was a lower spontaneous abortion rate and a higher multiple gestation rate when embryos were cultured in MEM.\nConclusion\nThus, MEM may result in healthier blastocyst development, especially when culture conditions are substandard, although this is not an acceptable substitution for meticulous technique.\nSimilar content being viewed by others\nReferences\nFishel SB, Cohen J, Fehilly C, Purdy JM, Walters DE, Edwards RG: Factors influencing human embryonic development in vitro.In In Vitro Fertilization and Embryo Transfer, M Seppala, RG Edwards (eds). New York Academy of Science, 1985, pp 342–356\nQuinn P, Kerin JF, Warnes GM: Improved pregnancy in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid. Fertil Steril 1985;44:493–498\nCummins JM: Comparison of two media in a human in vitro fertilization program: Lack of significant differences in pregnancy rate. J Vitro Fert Embryo Transfer 1986;3:326–329\nLopata A, Hay DL: The potential of early human embryos to form blastocysts, hatch from their zona, and secrete hCG in culture. Hum Reprod 1989;4:87–94\nLopata A, Hay DL: The surplus human embryo: its potential for growth, blastulation, hatching, and hCG production in culture. Fertil Steril 1989;51:984–991\nMuggleton-Harris AL, Findlay I, Whittingham DG: Improvement of the culture conditions for the development of human preimplantation embryos. Hum Reprod 1990;5:217–220\nSnyman E, Van der Merwe JV: Endotoxin-polluted medium in a human in vitro fertilization program. Fertil Steril 1986;46:273–276\nFishel S, Jackson P, Webster J, Faratian B: Endotoxins in culture medium for human in vitro fertilization. Fertil Steril 1988;49:108–111\nMontoro L, Subias E, Young P, Baccaro M, Swanson J, Sueldo C: Detection of endotoxin in human in vitro fertilization by the zona-free mouse embryo assay. Fertil Steril 1990;54:109–112\nRandall GW, Gantt PA: Preimplantation murine embryos are more resistant than human embryos to bacterial endotoxins. Vitro Fert Embryo Transfer 1990;7:280–282\nDumoulin JCM, Menheere PPCA, Evers JLH, Kleukers APG, Pieters MHEC, Bras M, Geraedts JPM: The effects of endotoxins on gametes and preimplantation embryos cultured in vitro. Hum Reprod 1991;6:730–734\nZarutskie PW, Dixon LL, Hiller SL: Identifying sources of bacterial endotoxin contamination in an in vitro fertilization culture environment. J Assist Reprod Genet 1992;9:77–80\nNg SC, Edirisinghe WR, Sathananthan AH, Ratnam SS: Bacterial infection of human oocytes during in vitro fertilization. Int J Fertil 1987;32:298–301\nDickey RP, Olar TT, Taylor SN, Curole DN, Rye PH, Matulich EM: Relationship of follicle number, serum estradiol, and other factors to birth rate and multiparity in human menopausal gonadotropin induced intrauterine insemination cycles. Fertil Steril 1991;56:89–92\nAuthor information\nAuthors and Affiliations\nRights and permissions\nAbout this article\nCite this article\nOlar, T.T., Potts, A.S. Effects of medium composition on murine and human blastocyst formation and hatching rate. J Assist Reprod Genet 10, 192–196 (1993). https://doi.org/10.1007/BF01239220\nReceived:\nAccepted:\nIssue date:\nDOI: https://doi.org/10.1007/BF01239220","source_license":"CC0","license_restricted":false}