Rome, because it puts absolute value on an unbreakable nexus between coitus and conception, forbids to its members all infertility treatment which bypasses the sexual union of man and woman. Rome, because it puts absolute value on human biological life from fertilisation, forbids all research and treatment which might cause the death of even the earliest pre-embryo. It rests these prohibitions on an authoritative declaration of what nature, God's divine order, requires. The authority cited is that given by tradition to the teaching office of the Church, supreme in the Pope. But not Rome only.
Some Evangelical churches are equally authoritative in their prohibitions.
Their authority is the Bible, God's word revealed, with mandatory force attached to texts sometimes quoted without regard to their historical, social or literary context as analysed in critical scholarship. This approach puts the sovereignty of God's will over all the pretensions of human will and the pursuits of human reason. God's sovereign will is known by revelation through the Bible, just as for the Vatican it is revealed through the magisterial teaching of the Church. In consequence Catholics and Evangelicals are found together in Europe, opposing such regulated experimental research and practice in fertility as is permitted by the law of England, the Human Fertilisation and Embryo Act 1990. The liberty guaranteed by the Act, and the duties imposed, were won by hard argument, in Parliament as in the country.