How Do the Chances of Success Differ Between a Fresh or Frozen Transfer?
As with all success rates, this varies from clinic to clinic. The most successful donor egg clinics these days are experiencing success rates of 50% and up (as measured by live birth rate per cycle initiated) on fresh cycles. Frozen transfers have lower success rates, possibly explained by a number of factors: 1. The number of embryos transferred on the average frozen embryo transfer (FET) is lower than the number of embryos transferred on a fresh cycle; 2. The best embryos are often transferred at the fresh cycle, so the frozen embryos may be of slightly worse quality; 3. The freeze/thaw process can thicken the “shell”, making implantation more difficult. Clinics are attempting to improve the statistics on FETs by doing assisted hatching on the embryos before transfer. In addition, a clinic may recommend that a recipient have more embryos transferred on a FET cycle than on a fresh cycle, although the patient is limited by the number of embryos available and the number that survive the
