Abstract
The Cochrane Pregnancy and Childbirth Database (CCPC) is the mostsophisticated realization of the meta-analyticpotential within the health fields. At the core of this ongoing collaborative international project are about 600 systematic reviews of the effectiveness of specificforms of perinatal care, which have been created from a registry of clinical trials. The scale and quality of information available through CCPC are unprecedented. An examination of implications of CCPC suggests that manyfar-reaching changes in perinatalpolicy andpractice are indicated. CCPChas become a model for similar work that is being organized in many other clinical areas under the umbrella of the pan-clinical Cochrane Collaboration, and the experience and implications of CCPC will be of interest to many working in other areas. The implications of these ambitious meta-analytic projects are profound; the degree to which they will be realized is less certain.