Ethical aspects of abortion

The ethical aspects of abortion are much discussed in all major philosophies and religions in the world, particularly (but not exclusively) in the Christian religion.

Comparitive rights
The feminist Beverly Harrison once said, "...the wellbeing of the woman and the value of her life plan should always be recognised as of intrinsic nature". Some would argue that a woman should have the right to control her own body. Therefore, she would be under no moral obligation to give birth, and should have self-determination in all reproductive matters.

Judith Jarvis Thomson, in her 1971 paper A Defense of Abortion, assumed for the sake of argument that personhood begins at conception. She went on to argue that the pregnant woman is under no moral compulsion to support a fetus against her desire, using an analogy in which the reader is asked to imagine awakening to find that they are being used as a living dialysis machine for a violinist who has suffered renal failure. Ultimately, Jarvis Thomson concludes, the right to consent outweighs the right to life in both cases. It has been argued that unless the violinist knowingly took part in this invasive procedure without the consent of the woman, the woman is not in a position to transfer her suffering to the violinist. It has been argued that pregnancy is only rarely the result of something unforeseeable and nonconsensual and even in those cases, it is not the child who has wronged the woman.

Those who are pro-life might argue that the sanctity of life extends to all humans. The right to life of the fetus would thus overrule the woman's right to choose abortion since abortion would be equivalent to murder. It is also argued that the right to life is an inalienable right that logically supersedes all other rights.

Question of personhood
Establishing the point in time when a zygote/embryo/fetus becomes a "person" is open to debate since the definition of "personhood" is not universally agreed upon.

Peter Singer argued that something can only be a person if it is self-aware and has temporal awareness. Therefore, abortion is morally acceptable, because a fetus does not meet this definition of personhood. Singer also concluded that infanticide would be permissible until the 3rd month after birth, because, at that point, self-awareness has still not been acquired.

A religious individual, on the other hand, might argue that one becomes a person at the moment of ensoulment. The precise point at which this event occurs, however, varies depending upon the religion, sect, or theologians.

Paul Ramsey and Charles Curran asserted that abortion, before 14th day of pregnancy, was acceptable, because after this point the division of the zygote through the process of monozygotic twinning becomes impossible. Current research suggests that fertilised embryos naturally fail to implant some 30% to 60% of the time. Of those that do implant, about 25% are miscarried in the first two to three weeks after pregnancy can be detected. Curran also suggested that the developing embryo should not be considered a person until its chance of survival to live birth was greater than one half.

In 1988, the Anglican Archbishop of York, John Habgood, argued that personhood begins with cellular differentiation.

The teaching of the Catholic Church holds that a human being's life begins at fertilization, and therefore abortion is always wrong. Because there are Biblical verses that can be interpreted to suggest that personhood begins at fertilization, this belief is generally held by other orthodox Abrahamic religions as well.

Sanctity of human life
In 1982, the late John Paul II said, in a speech pertaining to embryonic experimentation, "I condemn in the most explicit and formal way, experimental manipulation of the human embryo, since the human being, from conception to death, cannot be exploited for any purpose whatsoever". Members of the Catholic Church, in general, believe that all human life is sacred, and, thus, that the direct and intentional taking of an innocent human life is never a conscionable act.

However, a reverse argument could be made, in which factors that would reduce the future quality of life for the fetus to what might be defined as an insufferable degree could also be seen as violation of the sanctity of life.

If the pregnant woman's life is at risk, then, arguably, abortion could be viewed as the lesser of two evils. The Principle of Double Effect could thus be applied, as the intent of the abortion would be to preserve the life of the woman, and the death of the fetus would be a secondary consequence of this attempt.

The Catholic Church accepts the Principle of Double Effect when the death of the fetus is a secondary effect of treating the mother. For example, chemotherapy for cancer treatment may cause a miscarriage, and surgical removal of an ectopic pregnancy results in the death of the embryo. However, direct abortion with a side effect beneficial to the mother violates the Principle of Double Effect — so abortion prior to chemotherapy, or Methotrexate for ectopic pregnancy, are not acceptable.

Abortion from a utilitarian perspective
In the words of Jeremy Bentham, "The question is not can they reason nor can they talk, but can they suffer?" Thus, under the ethical theory of utilitarianism, people must consider the happiness of all those involved; actions must be chosen which will result in the greatest amount of good for the highest number of people.

From a more practical utilitarian perspective, abortion might be considered acceptable if performed within the period in which the fetus is incapable of experiencing pain, theorized to be around the 23rd week of gestation. Mifepristone, the "abortion pill," could be considered a painless method; prostaglandin abortion, on the other hand, could not, as it causes painful contractions in the woman and aborts the fetus through asphyxiation.

Abortion and natural law
According to the theory of natural law, reproduction is acknowledged to be an inherent component of the natural human condition (e.g., fertilization, differentiation and birth are all a part of the natural human life span), and, thus, abortion is counter to this design.

However, abortion can be seen as a furtherance of the human ability to reason. The aforementioned principle of double effect, in addition to proportionality, can also be used to justify abortion.