The history of the Catholic Church's position on the ordinary-extraordinary means distinction dates back to the 16 th century Dominican moralists. The tradition holds that an ordinary means of preserving life would be all medicines, treatments, and operations, which offer a reasonable hope of benefit for the patient and which can be obtained and used without excessive expense, pain, or other inconvenience. An extraordinary means would be all medicines, treatments, and operations, which cannot be obtained or used without excessive expense, pain, or other inconvenience, or which, if used, would not offer a reasonable hope of benefit. The distinctive element of the tradition is that it is a patient-centered, quality-of-life approach which is consistent with how the 16 th-century-Dominican moralists viewed this distinction. Therefore, a person is not morally obligated to use any means, and this would include natural or artificial means, that does not offer a reasonable hope of ameliorating the patient's condition. The ethical issue is whether this distinction can be applied to the issue of "frozen embryos." As a result of invitro fertilization it has been estimated that there are 500,000 spare embryos frozen with an additional 20,000 embryos added yearly. The issue is now what to do with the 500,000 frozen embryos that remain as "spares." Various alternatives have been suggested. The embryos could be thawed and then destroyed, continued to be cryopreserved indefinitely, used for embryonic stem cell research, or offered for donation/adoption. From the Catholic perspective, because these embryos are considered "human persons" it appears that the only viable ethical option would be to declare the process of cryopreservation an extraordinary means of life support, stop the process, allow the embryos to thaw and then to die naturally with dignity and respect.