There are good arguments for and against the practice.
Hundreds of thousands of frozen embryos left over from in vitro fertilization are waiting in storerooms of clinics and hospitals around the world for their future to be decided. Faced with this terrible situation, many Catholics ask themselves how they can help improve the situation, and many well-intentioned people point to the possibility of prenatal adoption—that is to say, that women could offer to bear these embryos and thus adopt them, before they are born, as their own children.
What does the Church say about this? It is true that there is no definitive decision regarding this difficult subject. However, in the latest Instruction on the dignity of the person in scientific matters, Dignitas Personae, (point 19), the Holy See indicates that prenatal adoption isn’t an ethically acceptable solution.
What is the reasoning behind this?
Dr. Justo Aznar, president of the Bioethics Observatory of the Catholic University of Valencia and member of the Pontifical Academy for Life, explains that the problem is that, in order carry out the adoption, it would be necessary to use techniques and procedures that are not ethically acceptable—the same ones used for "wombs for rent" or for "in vitro" fertilization. Therefore, although the ends are good, they do not justify acts that are intrinsically wrong.
"It’s not easy to admit that saving the life of a frozen embryo is an ethically incorrect stance," Dr. Aznar recognizes, "which is why some experts with well-formed consciences defend it. Anyway, since it is, in my opinion, still an open subject, it is possible that we might come to understand it better. This is why we will have to wait longer to know the definitive stance of the Magisterium on this topic." Yet it isbeyond a doubt that the Magisterium’s stance for the moment is against the adoption of frozen embryos.
What arguments are used by those in favor of adopting embryos?
Among the defenders of pre-natal adoption, there are highly prestigious Catholic researchers and doctors, such as Dr. Monica Lopez Barahona or Dr. Ramon Lucas, who have publicly shown support for this kind of adoption, since it means giving these embryos an opportunity to live. They are considered human persons with all their dignity and rights, despite having been conceived in a morally unacceptable manner.
The embryo’s life would therefore be a primary good which should be saved in order to make reparation for the injustice that has been committed against it when it was "produced" in a laboratory and then abandoned. Relative to its already disproportionate and "abnormal" situation, the means used to try to save the life should be seen as a "lesser evil."
In fact, for several years (especially between 2004 and 2006) in various Catholic media outlets and in Catholic universities that specialize in bioethics (in the USA and also in Italy and Spain), there was a heated debate about prenatal adoption. In 2008, the Instruction Dignitas Personae was therefore not the starting point, but the end point (although perhaps not the definitive one, but certainly a key one) of a wide and deep debate on the subject.
What are the arguments against it?
Dr. Aznar explains: "The Church is not in favor of this practice because, according to its judgment, it breaks the unity of the conjugal act, which is constituted by the conjugal relation of the spouses, the openness to life implied in this act, and the possibility that fertilization and then the corresponding pregnancy may occur. The Church believes that separating pregnancy from this integrated group of biological acts breaks that unity and therefore is not morally acceptable."