An evaluation of a modified slow cool cryopreservtion technqiue and the efficacy of a graduated estradiol regimen vs. Natural cycles on pregnancy rates following frozen embryo transfer

摘要

The purpose of the present study was to determine the efficacy of a modified and simplified slow cool cryopreservation technique in a large number of frozen embryo transfers. Furthermore, this retrospective study would attempt to determine the relative efficacy of graduated estrogen/progesterone replacement protocol vs. natural cycles. The slow cool technique replaced the planar programmable freezer with an alcohol bath controlled rate freezer and used a one step removal of the cryoprotectant upon thawing. Embryos were either frozen at the 2 pronuclear state or multi-cell day 3. Quite adequate live delivered pregnancy rates were found in women up to age 42 and even in women with diminished ovarian reserve. Both estrogen/progesterone replacement and natural cycle provided good pregnancy rates.