The basic concept emphasized in this book is that a coordinated, multidisciplinary approach within a regionalized system of perinatal care is a constant factor improving the quality of pregancy outcomes. This coordinated multidisciplinary approach has had an impact on perinatal care in three important areas: (1) improved and expanded understanding of the physiology and pathology of the pregnant women, fetus, and neonate; (2) improved health care through risk assessment and regional planning to ensure access to care; and (3) enhanced appreciation of the childbirth experience and the role of the family. The most current scientific information, professional opinions, and clinical practices have been assembled and reviewed in the formulation of this manual, which is intended to offer guidelines, not strict operating roles. Emphasis is placed on the delineation of areas to be covered by specific protocols (to be defined locally) rather than on promoting more rigid recommendations. To address issues and scientific advances that have emerged since the publication of the first edition, the second edition includes new sections devoted to such topics as Radiation Exposure and AIDS (acquired immune deficiency syndrome). (JD)