The moral status of the embryo is a controversial and complex issue. The main viewpoints are outlined below.
1. The embryo has full moral status from fertilization onwards
Either the embryo is viewed as a person whilst it is still an embryo, or it is seen as a potential person. The criteria for ‘personhood’ are notoriously unclear; different people define what makes a person in different ways.
Arguments for this view
Arguments against this view
Development from a fertilized egg into to baby is a continuous process and any attempt to pinpoint when personhood begins is arbitrary. A human embryo is a human being in the embryonic stage, just as an infant is a human being in the infant stage. Although an embryo does not currently have the characteristics of a person, it will become a person and should be given the respect and dignity of a person.
An early embryo that has not yet implanted into the uterus does not have the psychological, emotional or physical properties that we associate with being a person. It therefore does not have any interests to be protected and we can use it for the benefit of patients (who ARE persons).
The embryo cannot develop into a child without being transferred to a woman’s uterus. It needs external help to develop. Even then, the probability that embryos used for in vitrofertilization will develop into full-term successful births is low. Something that could potentially become a person should not be treated as if it actually were a person
2. There is a cut-off point at 14 days after fertilization
Some people argue that a human embryo deserves special protection from around day 14 after fertilization because:
After 14 days the embryo can no longer split to form twins. Before this point, the embryo could still be split to become two or more babies, or it might fail to develop at all.
Before day 14, the embryo has no central nervous system and therefore no senses. If we can take