What to Expect
One should expect recovery of an oocyte on approximately 75% of the attempts. Oocytes (eggs) fertilized through ICSI will divide and grow approximately 65-70% of the time, and pregnancy results from about 50% of the early embryos transferred. Oocyte quality and vigor decline with the donor mare’s age so that transfer of eggs from older donors tends to result in somewhat lower pregnancy rates than for young mares.