Catholicism

For most of its history, the Catholic Church taught that the primary purpose of God's gift of sexuality was the procreation and education of children. Occasionally other purposes of sexuality were noted, such as deepening the friendship of the married couple and helping to control excessive sexual desire. During the twentieth century biological science and technology made it possible to more effectively control the process of fertilization and the question arose whether Catholics might use these new methods of fertility control.

After extensive discussion involving bishops, theologians, and lay people, Pope Paul VI issued the encyclical letter, Humanae Vitae (On Human Life) in 1968. Before the issuance of that letter, many Catholics expected that the Catholic Church would change its rule of fertility control, which up to that time included only the use of natural methods. In brief, these methods allowed a couple to engage in sexual intercourse during infertile or safe times of the woman's cycle. Various methods of determining the precise time of infertility were developed to assist the couple in their quest for being responsible in the use of their procreative powers. New methods of fertility control developed in the years immediately preceding Humanae Vitae, the most well known being a pill that prevented ovulation. One of its developers was D. John Rock, who was a Catholic doctor.

The pope responded to this by saying that each and every act of sexual intercourse must be open to the creation of new life. In practice, that meant that the couple could not actively prevent possible fertilization from taking place. This teaching has been controversial for many Catholics. Nevertheless Pope John Paul II has strongly maintained the teaching of Pope Paul VI.

The Second Vatican Council reformulated and updated many teachings and practices of the church. In its document called Gaudium et Spes (The Pastoral Constitution on the Church in the Modern World) it devoted a lengthy section on what it labeled The Dignity of Marriage and the Family. Here it expanded on the meaning of human sexuality in marriage by saying that it is both an expression of marital love, and it is an act that potentially could generate new human life. The church left behind any language of primary or secondary meaning to marital sex. It took a "bothand" approach in affirming two essential purposes of human sexuality. Many pastors, theologians, and married couples welcomed this broader understanding, which clearly valued human sexuality as essentially expressive of marital love.