Moving to blastocyst biopsy for preimplantation genetic diagnosis and single embryo transfer at Sydney IVF.

Developments at Sydney IVF in the successful culture of blastocysts, combined with day 5 or 6 blastocyst biopsy and blastocyst cryostorage after biopsy, permit up to five or six cells to be genetically tested, leaving the inner cell mass intact and enabling embryos to be electively transferred one at a time. These advantages can be obtained without diminishing the chance of pregnancy compared with cleavage-stage biopsy and testing.