Timed oocyte collection in an assisted conception programme using GnRH analogue.

Three-hundred-and-twenty-five patients on an assisted conception programme underwent 378 cycles of oocyte retrieval (OPU) following ovarian stimulation using a GnRH analogue and human menopausal gonadotrophins (HMG), a regimen which allows programmed cycles and delayed oocyte retrieval. Eighteen cycles were excluded (failed OPU in three and failure of fertilization in 15). In 360 cycles, patients completed their treatment with either in-vitro fertilization/embryo transfer (IVF/ET) (116) or gamete intra-Fallopian transfer (GIFT) (244), of which 241 took place at the normal time and 119 were delayed for 24 h or more to avoid weekend operating. The overall pregnancy rate per OPU was 29.5%, with the IVF group being 24.1% and the GIFT group being 32.8%. In the group of patients in whom OPU was delayed, the pregnancy rate was significantly higher in each sub-group than in the corresponding non-delayed sub-group (overall, 37.0 versus 25.7%; IVF/ET, 38.5 versus 16.9%; GIFT, 36.3 versus 31.1%). There was a significantly higher number of oocytes collected, gametes/embryos transferred in the group whose OPU had been delayed. In patients receiving GnRH analogue and HMG for ovarian stimulation, delaying oocyte retrieval is not harmful, may result in an improved outcome and allows OPU to be performed on routine operating lists. This facility, together with the improved pregnancy rates associated with this protocol of ovarian stimulation should improve the cost-effectiveness of assisted conception programmes.