Book excerpt: EUROPEAN PRACTICE IN GYNAECOLOGY AND OBSTETRICT is a series of books conceived and endorsed by the European Board and College of Obstetrics and Gynaecology (EBCOG). Its aim is to provide up-to-date, evidence-based information that represents the consensus of opinion among leading European experts in the field, as part of the overall aim of standardising training and practice in order to ensure quality care and facilitate exchange among physicians in all parts of Europe and the rest of the world.