Although freezing of embryos using conventional techniques is a relatively successful treatment for many infertile couples, the freezing of oocytes has always been difficult. Preliminary research using a newer method of freezing (vitrification) for eggs has shown promise. At the Reproductive Center, we have comparable fertilization rates with fresh IVF or IVM cycles and frozen eggs. More than 200 healthy babies have been born around the world following vitrification freezing of oocytes, but oocyte survival following vitrification is still unstable. Furthermore, as with any new infertility procedure, there may be potential congenital or developmental problems. Therefore, appropriate monitoring and surveillance during pregnancy, delivery and childhood needs to be instituted.
If vitrification of oocytes can be made more efficient, there are several potential benefits for the patients: Firstly, it will allow young women who are about to undergo chemo/radiotherapy for cancer to store their eggs for fertility conservation prior to treatment. Secondly, it will allow a woman to store her eggs before any operation for gynecological diseases that may damage her ovaries and possibly delay pregnancy. Thirdly, egg freezing avoids several of the complex ethical, social and legal dilemmas that are sometimes associated with embryo freezing.
The purpose of the present study is to investigate the efficacy of oocyte cryopreservation with Vitrification using different FSH preparations during IVF or without any stimulation in in vitro maturation (IVM).
This is a prospective pilot study to determine treatment efficacy among a total of 120 study patients. Oocytes will be retrieved by our standard protocol, and frozen immediately by the method of vitrification. The oocytes will then be thawed when the patients are ready for embryo transfer in the following menstrual cycle and the surviving oocytes will be inseminated by ICSI.
Funding: partially by Schering-Plough Canada Inc