Nearly 50 years after the introduction of cardiotocography (CTG) into routine clinical practice, many uncertainties still surround the various forms of intrapartum fetal monitoring and the related decision-making process. Intrapartum fetal hypoxia/acidosis continues to account for a high percentage of perinatal deaths and long-term neurological sequelae, both of which have a significant negative impact on the families and on health-care professionals. The widespread interest that surrounded this area of knowledge in the 1970s and 1980s gave way to a period of lesser attention and slower progress. However, the topic has recently regained a central role in obstetrics, and several important developments have taken place over the last decade.

This issue of Best Practice and Research in Clinical Obstetrics and Gynecology reviews the basic principles of intrapartum fetal surveillance and provides an update on the most recent developments in the area. The introductory article describes the importance of maintaining oxygen supply to the fetus during labour and the main aims of intrapartum fetal monitoring, listing the adverse outcomes that need to be avoided, together with unnecessary obstetric intervention. A more detailed review of the pathophysiology of fetal oxygenation during labour and the pathways of cell damage is provided in the second article. A sound knowledge of the main technical characteristics of current CTG monitors is required for a comprehensive use of the method, and these aspects are reviewed in the third article. Interpretation of CTGs and subsequent clinical management plays a central role in intrapartum fetal surveillance, and these aspects are described in detail in the fourth article, with particular emphasis on a worldwide consensus that has recently been published. The fifth and sixth articles review the existing evidence on the use of adjunctive technologies to CTG, aimed at reducing the high number of false positives in the latter. The combined use of CTG + ST monitoring and of fetal blood sampling during labour for fetal pH and lactate measurements is described. Visual analysis of CTGs and CTG + ST signals is prone to wide interobserver and intra-observer disagreement, and computer systems have evolved over the last decade to provide automated analysis of intrapartum tracings. The seventh article provides a detailed review of currently existing systems for computer analysis of CTG and CTG + ST signals.

In the eighth chapter, the different types of short- and long-term neurological damage to the fetus arising from intrapartum hypoxia/acidosis are revisited from an obstetric perspective. Intrapartum fetal surveillance has faced frequent malpractice claims, and the main aspects surrounding the litigation process are evaluated in the ninth article. Finally, the tenth article presents an experienced personal view on future perspectives in intrapartum fetal monitoring.

Health-care professionals, with their knowledge and skills, remain the most important factor in high-quality intrapartum care, and this is likely to continue for many years to come. It should be remembered that an adequate clinical response to suspected fetal hypoxia/acidosis is probably the factor most directly related to neonatal outcome. This response involves the use of not only appropriate knowledge and technical skills but also good communication and teamwork. Therefore, regular training of the labour ward staff needs to be considered as a key factor in intrapartum fetal surveillance, which is essential to guarantee positive neonatal outcomes and reduced intervention rates.

Intrapartum fetal surveillance is only one of the many aspects of intrapartum care, but fetal safety is an evident prerequisite for establishing a positive environment during the birthing process. Therefore, a profound knowledge of intrapartum fetal surveillance and of the related decision-making process is essential to guarantee a fulfilling experience for labouring women and their families during this important moment of their lives.