The moral significance of these two dimensions - the procreative and the unitive dimensions of marital love - becomes most clearly manifest in marital sexual intercourse. In this context, it becomes easier to understand why the unitive and procreative dimensions of marital intercourse may never be intentionally separated.
Such was the core teaching of Paul VI's encyclical Humanae Vitae. Human beings cause themselves and others grave harm when they sever the "unbreakable connection" between the unitive and procreative dimensions of marital sexual intercourse.
Consequently, as explained in DV, it is morally wrong for married couples or anyone to attempt to generate human life outside of, or apart from, the act of marital sexual intercourse because to do so severs those dimensions: in IVF, procreation takes place in a Petri dish, apart from the unitive dimension of conjugal act.
(2) A second argument is based on considerations of the dignity of the child conceived by these means. DV argues that bringing a child into existence as a product of a technique is to render that child an object. Children brought into the world through IVF are arguably not generated, but manufactured. While the couple provides the 'materials' (ovum and sperm) for the creation of the child, it is a laboratory technician who brings about a new human life in a laboratory dish. The Church further teaches, that in light of this same human dignity, every human being possess a right to be "conceived and born within marriage and from marriage."
(3) A further argument against IVF has to do with the consequences of the procedure. There are well documented health risks -- which have on occasion been lethal -- to women who undergo super-ovulation for the retrieval of their eggs for IVF purposes. Add to this, as reported in Scientific American last February, mounting scientific evidence points to the troubling fact of genetic abnormalities in children born through recourse to IVF. At present, some three million IVF children have come into the world since the procedure was first used in 1978. While most are healthy, studies indicate that they are at risk for certain kinds of birth defects and for the onset later in life of obesity, hypertension and type 2 diabetes. Finally, even if these risks were nonexistent, IVF still normally brings about the grave injustice of leaving an orphaned population of unwanted embryos to the absurd fate of frozen storage and eventual destruction.
The Church fully supports the endeavors of physicians such as Dr. Thomas Hilgers, director of the Pope Paul VI Institute for the Study of Human Reproduction. His natural methods of overcoming infertility, known as NaPro Technology, have helped hundreds of couples to achieve a pregnancy without recourse to illicit means. While no couple has a 'right' to a child, they should be afforded all the means licit and available to help them achieve a pregnancy to the extent possible.
