Article
Human oocyte cryopreservation: 5-year experience with a sodium-depleted slow freezing method

https://doi.org/10.1016/S1472-6483(10)62021-4Get rights and content

Abstract

A slow freezing/rapid thawing method for the cryopreservation of human oocytes has been employed using a sodium-depleted culture media. In 53 frozen egg-embryo transfer (FEET) cycles, a 60.4% survival rate post-thaw was obtained and a 62.0% fertilization rate following intracytoplasmic sperm injection. Overall pregnancy rates were 26.4% per thaw attempt, 30.4% per patient, and 32.6% per embryo transfer. Pregnancy rates using sodium-depleted phosphate-buffered saline (PBS) as the base medium were 20.0% per thaw, 21.7% per patient, and 26.3% per transfer. With sodium-depleted modified human tubal fluid (mHTF) as the base for the cryopreservation medium, rates were 32.1% per thaw attempt, 39.1% per patient, 37.5% per transfer. The overall implantation rates were 4.2% per thawed oocyte and 13.6% per embryo, (PBS: 3.0% per egg, 10.6% per embryo; mHTF:5.3% per oocyte; 15.9% per embryo). These data indicate that the use of a sodium-depleted media with slow freezing and rapid thawing can yield acceptable pregnancy rates after FEET.

Section snippets

Dr Boldt is Scientific Director of Assisted Fertility Services at Community Health Networks in Indianapolis. He is also Scientific Director of CryoEggs International (a commercial frozen oocyte bank), President/CEO of The Reproductive Technology Group (providing data and laboratory management to infertility programs), and is Clinical Associate Professor of Medical and Molecular Genetics at Indiana University School of Medicine. Dr Boldt has been active in clinical embryology since 1983, and has

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    Dr Boldt is Scientific Director of Assisted Fertility Services at Community Health Networks in Indianapolis. He is also Scientific Director of CryoEggs International (a commercial frozen oocyte bank), President/CEO of The Reproductive Technology Group (providing data and laboratory management to infertility programs), and is Clinical Associate Professor of Medical and Molecular Genetics at Indiana University School of Medicine. Dr Boldt has been active in clinical embryology since 1983, and has published over 30 articles and book chapters in basic and clinical reproductive biology.

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