In many parts of the world abstinence from sexual activity before marriage is valued. In other societies adults (and many adolescents) are unwilling to sacrifice the principle of abstinence even if general practice is different.
Today there are many who vindicate the right to sexual union before marriage, at least in those cases where a firm intention to marry and an affection which is already in some way conjugal in the psychology of the subjects require this completion, which they judge to be connatural. This is especially the case when the celebration of the marriage is impeded by circumstances or when this intimate relationship seems necessary in order for love to be preserved. This opinion is contrary to Christian doctrine, which states that every genital act must be within the framework of marriage. However firm the intention of those who practice such premature sexual relations may be, the fact remains that these relations cannot ensure, in sincerity and fidelity, the interpersonal relationship between a man and a woman, nor especially can they protect this relationship from whims and caprices. Sexual union therefore is only legitimate if a definitive community of life has been established between the man and the woman. These requirements call for a conjugal contract sanctioned and guaranteed by society – a contract which establishes a state of life of capital importance both for the exclusive union of the man and the woman and for the good of their family and of the human community. Most often, in fact, premarital relations exclude the possibility of children. What is represented to be conjugal love is not able, as it absolutely should be, to develop into paternal and maternal love. Or, if it does happen to do so, this will be to the detriment of the children, who will be deprived of the stable environment in which they ought to develop in order to find in it the way and the means of their insertion into society as a whole. (Sacred Congregation for the Doctrine of the Faith: Persona Humana, 1975).