Developmentally delayed cleavage-stage embryos maintain comparable implantation rates in frozen embryo transfers.

Purpose: In fresh IVF cycles, embryos reaching the eight-cell stage on day 3 of development are thought to have a higher chance of implantation than those reaching this stage on day 4. To determine whether this difference persists after cryopreservation, we compared pregnancy and implantation rates between frozen embryo transfer (FET) cycles using delayed cleavage-stage embryos (cryopreserved day 4) and normal cleavage-stage embryos (cryopreserved day 3).

Methods: Participants underwent FET between 2008 and 2012 using embryos cryopreserved on either day 3 (n = 76) or day 4 (n = 48), depending on the length of time needed to achieve the eight-cell stage.

Establishment of a nonanonymous donor oocyte program: preliminary experience at the University of Southern California.

Transvaginal ultrasound-directed oocyte retrieval was performed on eight women functioning exclusively as gamete donors for 10 patients with ovarian failure. Donors included sisters, personal friends, and compensated participants selected by the recipient couple. Oocyte donors underwent controlled ovarian hyperstimulation and transvaginal oocyte aspiration.