There has seemed to be a great deal of disagreement among the medical authorities who have attempted to say when a woman should not have children. This disagreement has been rendered even more confusing by a babel of voices from the ranks of sociologists. Within the past few years, however, so much light has been shed upon the subject that it is now comparatively easy for the student to separate the well-founded conclusions from those which are of doubtful value, or plainly worthless. The opinions which I summarize here are not so much my own, originally, as those of medical authorities who have made deep and careful investigations. There is, however, nothing set forth here which I have not in my own studies tested and proved correct. In addition to carrying the weight of the best medical authority, a fact easily confirmed by the first specialist you meet, they are further reinforced by the findings of the federal Children's Bureau, and other organizations which have examined infant mortality and compiled rates. To the woman who wishes to have children, we must give these answers to the question when not to have them. Childbearing should be avoided within two or three years after the birth of the last child. Common sense and science unite in pointing out that the mother requires at least this much time to regain her strength and replenish her system in order to give another baby proper nourishment after its birth. Authorities are insistent upon their warnings that too frequent childbearing wrecks the woman's health. Weakness of the reproductive organs and pelvic ailments almost certainly result if a woman bears children too frequently. By all means there should be no children when either mother or father suffers from such diseases as tuberculosis, gonorrhea, syphilis, cancer, epilepsy, insanity, drunkenness and mental disorders. In the case of the mother, heart disease, kidney trouble and pelvic deformities are also a serious bar to childbearing. Thousands of volumes have been written by physicians upon the danger to mothers and offspring of having children when one or both parents are suffering from the diseases mentioned above. As authorities have pointed out in all these books, the jails, hospitals for the insane, poorhouses and houses of prostitution are filled with the children born of such parents, while an astounding number of their children are either stillborn or die in infancy.