AN INTRAUTERINE INSEMINATION-READY CRYOPRESERVATION METHOD COMPARED WITH SPERM RECOVERY AFTER CONVENTIONAL FREEZING AND POSTTHAW PROCESSING

Objective: To test a sucrose-glycerol cryoprotectant for IUI-ready spe rm preparation. Design: Semen aliquots from normozoospermic donors eit her were subjected to conventional semen freezing (TES and Tris yolk b uffer in 7.4% final glycerol) with post-thaw processing or were prepro cessed and frozen in HEPES-buffered human tubal fluid with 1% human se rum albumin, 4% sucrose, and 6% glycerol. All aliquots were cooled to 4 degrees C, exposed to liquid nitrogen vapors, and stored in liquid n itrogen. Aliquots from each were processed by centrifugation resuspens ion or by centrifugation in Percoll (Pharmacia, Alameda, CA) before sp erm parameters were analyzed. Setting: University-based andrology labo ratory. Main Outcome Measure(s): Recovery of motile sperm. Result(s): Percoll processing produced preparations with higher percentages of mo tile cells; however, cryopreserved sperm had a lower recovery of motil e sperm compared with Percoll-processed fresh semen or centrifugation/ resuspension-processed fresh or frozen samples. The percentages of spe rm with normal morphologies were significantly increased in the IUI-re ady samples compared with samples frozen conventionally. The IUI-ready Percoll-processed sample produced the best results, with a final mean motility of 36% and an overall yield of motile sperm of 17.4%. Conclu sion(s): The sucrose-glycerol-based cryoprotectant produced an IUI-rea dy preparation with motile sperm recovery comparable to that of conven tional semen cryopreservation but with improved percent morphology. (C ) 1997 by American Society for Reproductive Medicine.