Pregnancies after replacement of frozen-thawed embryos in a donation program

Eighteen patients with primary (n = 8) or secondary (n = 10) ovarian failure were enrolled in a donation program. In 15 cases, the oocytes were donated anonymously; in 3 cases, they were donated by the sister of the recipient. All the recipients had cyclic steroid replacement therapy that included estrogens and progesterone administered by the transdermal and tranvaginal routes, respectively. The embryos obtained were cryopreserved and replaced with no attempt at synchronization between donor and recipient. Steroid hormonal patterns were within the range for the normal menstrual cycle and endometrial biopsies taken on day 21 or 22 of the treatment cycles were independently assessed as being representative of day 21 +/- 2. Four of 12 transfers were successful (31%): 1 patient aborted at 6 weeks, and the three others were delivered, one normally and two by cesarian sections. The authors' practice suggests the following: (1) steroid supplementation by transdermal and transvaginal routes is effective, (2) synchronization between donor and recipient is no longer required with the use of frozen-thawed embryos, and (3) the "temporal window" is large since all the replacements were done on day 14 of the cycle.