An improved fixation technique for fluorescence in situ hybridization for preimplantation genetic diagnosis

Objective: To improve existing preimplantation genetic diagnosis fixation techniques. Design: Prospective randomized in vitro study. Setting: Academic medical center. Patient(s): None. Intervention(s): None. Main Outcome Measure(s): The intensity and clarity of fluorescence in situ hybridization (FISH) signals and the percentage of successfully fixed blastomeres. Result(s): The described fixation technique resulted in 100% fixation and 100% adequate FISH signals. Two conventional techniques resulted in 94% and 87% fixation, and in adequate FISH signals in 81% and 87%, respectively. Conclusion(s): This newly developed fixation technique simplifies the process of fixation of blastomeres for preimplantation diagnosis while essentially eliminating the possibility of losing a cell during fixation. It will hopefully allow more IVF programs to offer their patients preimplantation genetic diagnosis using the FISH technique. (C) 2001 by American Society for Reproductive Medicine.