Embryo freezing: ethical issues in the clinical setting.

Embryo Freezing: Ethical Issues in the Clinical Setting Only four years ago, embryo freezing (cryopreservation) was considered a technique raising "disturbing," "extremely difficult," "incredibly complex," and even "nightmarish" ethical issues. Currently, however, at least 41 of the 169 infertility clinics in the United States have added freezing to in vitro fertilization (IVF) protocols. [1] The number of frozen embryos in this country nearly tripled from 289 to 824 between 1985 and 1986. [2] An estimated ten infants in the U.S. and sixty in the world were born as of 1988 after having been frozen as embryos. [3] Some physicians have concluded that freezing eliminates ethical dilemmas by allowing embryos to be stored rather than discarded, and researchers have contended that freezing poses few unique dilemmas. [4] It is true that if we look for evidence of public ethical controversy, predictions of perplexing quandaries have not, apart from the case of the Rios's "orphaned" frozen embryos in Australia, been realized. In the clinical setting, however, unanswered questions suggest the need to keep alive the ethical debate about the benefits to patients and society of embryo freezing. Questionable Benefits During a woman's initial IVF cycle, three or four of the embryos created are transferred to her uterus, while the rest are frozen for storage, to be thawed and transferred at a later date. Practitioners of IVF justify freezing as enhancing their ability to act in the patient's best interest. [5] In general, they presume freezing will benefit the patient physically, emotionally, and financially. In theory, because not all embryos need be transferred in the first IVF cycle, freezing physically benefits a woman undergoing IVF by reducing the odds that a multiple pregnancy will occur--letting the patient recover from the stress of IVF before a second transfer of embryos, and sparing her repeated ovarian hyperstimulation and egg retrieval surgeries (laparos-copies). [6] It furthers the patient's emotional needs by reducing anxiety when she knows she has succeeded in one part of IVF and has tangible evidence, in the form of stored embryos, of that success. Finally, the patient benefits financially in that freezing avoids repeated start-up IVF expenses of hormonal monitoring, laparoscopy, and time lost from work during the two-week IVF cycle. There is a real distance between theory and practice, however. Clinics report freezing an average of fewer than three embryos per patient. From one-quarter to one-half of these embryos do not survive freezing and thawing in established centers, and the attrition rate is undoubtedly higher in newer centers. Thus an optimal scenario of freezing, in which around six embryos are stored for leisurely transfer over a period of months, has yet to be realized. [7] Does freezing actually benefit the patient physically? No injuries such as uterine infections from the transfer of thawed embryos have been reported, but neither does the evidence demonstrate that freezing significantly reduces the physical stresses from IVF for patients. There are insufficient data to conclude whether the use of thawed embryos is correlated with fewer miscarriages or multiple pregnancies. Moreover, the reduction of hormonal stimulation and laparoscopy may be less than expected, since mild medication may be needed to prepare the uterus for embryo transfer with thawed embryos. [8] And due to the attrition rate of frozen embryos, the patient may have to undergo the rigorous initial IVF cycle only to be spared, at most, one repeat cycle. Does freezing benefit patients emotionally? Physicians presume that patients build defenses against disappointment when embryos are stored, but some women do just the opposite and "enhance" the embryos by coming to see them as babies. Patients may develop attachments to their embryos during regular IVF, as indicated by their naming the embryos, asking for the petri dishes in which the embryos were fertilized as mementoes, acting and feeling pregnant after the embryos are transferred to their uteruses, and mourning the embryos' loss if they do not implant. …