This book outlines the history of rickets, a disease commonly associated with childhood, and studies its association with race and its long-reaching effects on childbirth. For centuries, the condition was recognized but poorly understood. For females, rickets could pose a double jeopardy: suffering in childhood and severe danger in adulthood when giving birth. The disease could result in a contracted pelvis that obstructs the birth canal. Medical researchers were faced with two distinct challenges: unravelling the aetiology of rickets and ensuring the safety of women giving birth. Solving the riddle of rickets proved especially difficult. Thought variously to be a disease of industrial cities and children of the poor, grounded in lack of exercise or sunlight, or the product racial difference, the condition defied analysis until the discovery of vitamin D early in the 20th century. The dangers of rickets radically diminished. Medical intervention in childbirth continued, and birth increasingly shifted from the home to the hospital. Medical practitioners justified intervention by emphasizing the dangers of pelvic disproportion, continually enlarging the definition to gain full control of birth. Often conditioned by racial assumptions, surgical experimentation promoted common use of anaesthesia and a radical increase in caesarean sections, and birth became a colder, more clinical experience.