Mouse in vitro fertilization, embryo development and viability, and human sperm motility in substances used for human sperm preparation for assisted reproduction

Objective: To investigate the endotoxin content and effects on mouse IVF and emhryo development and human sperm motility of human sperm separation substances. Design: One-cell and zona-free two-cell mouse embryo bioassays and Limulus Amoebocyte Lysate endotoxin tests and mouse oocyte parthenogenetic activation, IVF, preimplantation and postimplantation embryo development, and human sperm motility were performed in control medium or medium containing Percoll, Nicodenz, or the washings from Sperm Prep sephadex columns. Setting: Research Laboratories, Sinai Hospital of Baltimore, Baltimore, Maryland. Main Outcome Measure(s): Endotoxin levels, embryo development, and sperm motility. Result(s): Mouse embryo bioassays indicated negative endotoxin levels in Percoll and Nicodenz but Limulus Amoebocyte Lysate assays had positive gel formation. Mouse IVF and preimplantation development was equivalent in control and Percoll- and Nicodenz-containing medium; none had parthenogenetic properties but postimplantation development was reduced for embryos grown in the presence of Percoll or Nicodenz. Human sperm remained motile in the presence of Percoll or Nicodenz. Sperm Prep column washes were toxic to mouse gametes and embryos and human sperm and had gel formation with the Limulus Amoebocyte Lysate assay. Conclusion(s): Percoll and Nicodenz, but not Sperm Prep sephadex column washes, were compatible with mouse preimplantation and postimplantation embryo development and human sperm motility.