In writing this book I have attempted to follow the gen­ eral pattern of the lectures which I have given to pupil midwives at Worcester Royal Infirmary for the past 21 years. In hospital it has been possible to illustrate what I have had to discuss by reference to cases at present in the wards. This unfortunately is not possible to the same extent in a book, but I have no doubt that my readers will be able to apply the principles described to cases under their care. I am sure that this is a most helpful way of fixing in one's mind the information which is required not only for examination purposes but so much more importantly for the better understanding of the clinical problems with which one is faced, and for the purpose of bringing to them the best possible management. The chapter headings and the arrangement of the chapter content may be regarded as unorthodox, but I have presented the topics in the way in which they seem to me to arise in clinical practice. This, I hope, will make easier the understanding of all aspects of a problem. [ have tried to avoid duplication, and when a topic appears in more than one place, it does so in order to discuss its relevance in a different context. Cross-references have been used throughout the text, in order to facilitate reference to the other facts of importance.