DOI link for Sexual Periodicity
Sexual Periodicity book
TH E periodicity of growth and of reproductive life is more arresting than perhaps any other vital phenomenon. Nine months’ intra-uterine gestation precedes a man’s birth into the external world. Two years pass before he walks into a childhood that extends to puberty at fourteen, when his sexual organs first become active. In women reproductive life is divided into 2 8-day cycles, periods of pregnancy and nursing, and is curtailed by a menopause long before old age. In men it continues evenly and without interruption until they are overtaken by senility. The normal periodicity of all these phenomena is fixed within narrow and still inexplicable limits. There is no obvious reason why the human sexual cycle should take four weeks instead of six, and why gestation should last ten instead of five lunar months. At present there seems no more reason for the particular rhythm of these phenomena than there is for life itself. The rhythmical nature of physiological events is part of their make-up; the most that can be discovered by available methods about periodicity is the mechanism of its maintenance.