humanae-vitae

A child deserves to be born of that love, and not by any other means, for __e or she is not something owed to one, but is a gift_, which is __he fruit of the specific act of the conjugal love of the parents_. This is the case because, __ccording to the order of creation, conjugal love between a man and a woman, and the transmission of life are ordered to each other (cf. Gen 1:27-28). Thus the Creator made man and woman share in the work of his creation and, at the same time, made them instruments of his love, entrusting to them the responsibility for the future of mankind, through the transmission of human life_.