120 If, however, for this purpose, private resources do not suffice, it is the duty of the public authority to supply for the insufficient forces of individual effort, particularly in a matter which is of such importance to the common weal, touching as it does the maintenance of the family and married people. If families, particularly those in which there are many children, have not suitable dwellings; if the husband cannot find employment and means of livelihood; if the necessities of life cannot be purchased except at exorbitant prices; if even the mother of the family to the great harm of the home, is compelled to go forth and seek a living by her own labor; if she, too, in the ordinary or even extraordinary labors of childbirth, is deprived of proper food, medicine, and the assistance of a skilled physician, it is patent to all to what an extent married people may lose heart, and how home life and the observance of God's commands are rendered difficult for them; indeed it is obvious how great a peril can arise to the public security and to the welfare and very life of civil society itself when such men are reduced to that condition of desperation that, having nothing which they fear to lose, they are emboldened to hope for chance advantage from the upheaval of the state and of established order.
Source: Casti Connubii (Vatican.va)