transforms the egg cell into a 'zygote'."; respect for life at all stages, even potential life, is generally the context of church documents. Abortion has been specifically and persistently condemned by the Church since the first century. "Formal cooperation" in abortion incurs the penalty of excommunication "by the very commission of the offense" (Lat. latae sententiae, "sentence [already, i.e. automatically] passed"). The Catechism emphasizes that this penalty is not meant to restrict mercy, but that it makes clear the gravity of the crime and the irreparable harm done to the child, its parents and society. "Formal cooperation" in abortion extends not just to the mother who freely submits, but also to the doctor, nurses and anyone who directly aids in the act. The Church has ministries of reconciliation, such as Project Rachel, for those who sincerely repent of their sin of formal cooperation in abortion. Official Church teaching allows for medical procedures and treatments intended to protect or restore the mother's health if she would be in mortal danger without them, even when such procedures carry some risk of death to the fetus. Examples include the removal of a fallopian tube in the case of an ectopic pregnancy, removal of a pregnant cancerous uterus, or an appendectomy. Use of embryos for research or fertilization The United States Catechism for Adults devotes a section to in vitro fertilization, stem-cell research and cloning in its explanation of the fifth commandment, because these often involve the destruction of human embryos, considered to be a gravely sinful form of murder. Embryonic stem cell research is called "an immoral means to a good end" and "morally unacceptable." Citing the Congregation for the Doctrine of the Faith's Instruction on Respect for Human Life in its Origin and on the Dignity of Procreation, the US Bishops quote: "No objective, even though noble in itself, such as a foreseeable advantage to science, to other human beings, or to society, can in any way justify experimentation on living human embryos or fetuses, whether viable or not, either inside or outside the mother's body." The Bishops note that adult stem cell research, using cells obtained with informed consent, is a promising field of research that is morally acceptable. Suicide, euthanasia The fifth commandment forbids suicide and the mercy killing of those who are dying, even to eliminate suffering. The ordinary care of those facing an imminent death may not morally