Embryo donation, also at times called embryo adoption, entails the transfer of eggs previously fertilized by one woman’s partner (or sperm donor of her choice) into the uterus of another infertile woman. From a technical point of view embryo donation is analogous to egg donation except that the donation takes place after fertilization has occurred. From a genetic point of view embryo donation is analogous to adoption inasmuch as neither Intended Parent provides the gametes (egg and sperm); thus the child has no genetic link to the Intended Parents. Whereas in theory both fresh and frozen embryos can be donated, in practice most donated embryos to date have been frozen (What Is Involved in Embryo Freezing?).
It is unknown how many embryo donation transfers are done each year in the United States. The annual national SART and CDC reports do not designate embryo donation as a separate ART procedure. Thus embryo donation is subsumed within the much larger category of frozen embryo transfers. The exact success rate of embryo donation is also unknown but is likely to be comparable to the live birth rate per frozen transfer which in 2006 was about 26% nationally. Historically, embryo donation is a by-product of embryo freezing technology which in turn was necessitated by the widespread use of vigorous ovarian stimulation with production of multiple eggs and embryos.
One of the common misconceptions is that thousands of frozen embryos have been donated and are available in ART clinics throughout the world. Whereas a large number of embryos have been frozen in the 400+ IVF clinics in the United States, relatively few of these embryos have been donated.
In our experience only a relatively small percentage of frozen embryos from traditional IVF are donated. In a pioneering study we conducted a few years back, we found that the disposition of the “spare embryos,” which were not used by the original patients, was very different depending on the source of the eggs. Following IVF with the woman’s own eggs, the spare embryos were four times more likely to be destroyed than donated. After treatment with donor eggs, on the other hand, spare embryos were much more likely to be donated than destroyed (Dr. Chetkowski’s CV, Publications #22 and 26).
Embryo donation is seldom the fertility procedure of first choice. It is rare that a couple would initially select donated embryos as their preferred method of building a family. Embryo donation makes most intuitive sense for single women who require the use of both donor eggs and donor sperm (Single Parents). Couples who have undergone multiple failed IVF cycles often pursue embryo donation before moving on to adoption. Since most of the work and expense involved in assisted fertilization has already been incurred, donated embryos are also relatively less expensive than other ARTs. From a purely technical point of view embryo donation is no different from other frozen embryo transfers (IVF & Frozen Embryo Transfer).