Epidemiology of Fetal and Neonatal Death

Abstract

Introduction: A perinatal death refers to fetal or neonatal death, combined to calculate the perinatal mortality rate. High perinatal mortality rates indicate unmet public health needs and also deficiencies in clinical care provision. The death of a child around the time of birth has profound effects on parents and families. Increasing attention is being paid to reducing these deaths. Epidemiological analyses aid in the identification and monitoring of prevention strategies.

 Objectives: This chapter provides an overview of the epidemiology of fetal and neonatal death globally including numbers, rates, causes, and risk factors and highlights issues that limit the utility of perinatal mortality as a measure of health and quality of care including classification systems to assign causes of perinatal deaths.

 Key Points: An estimated 2.9 million neonatal deaths and 2.6 million late gestation stillbirths (after 28 weeks of gestation) occur globally each year. These numbers almost double when using the definitions of stillbirths and neonatal deaths of high-income countries (i.e., from 20 weeks of gestation). The vast majority of these deaths occur in low- and middle-income countries and are avoidable. Since 1990, the global neonatal death rate has decreased by 37 %, from 33 to 21 deaths per 1,000 livebirths; however, this is slower than the 50 % reduction in deaths in the postneonatal period up to the age of 5. The decline in the stillbirth rate has been slower: an estimated 14.5 % reduction from 22.1 to 18.9/1,000 (1995–2009). Wide variation in rates exists within and across countries. The majority of deaths occur in the 24 h around the time of birth, where increased access to quality obstetric and newborn care could halve these deaths. The lack of data on numbers and causes of death plagues prevention efforts. Further, the use of numerous disparate classification systems makes interpretation of causes of perinatal deaths difficult. However, placental pathology (including abruption and insufficiency) often associated with growth restriction is clearly a major contributor to stillbirth globally, in addition to low-income settings, hypertensive disorders, and infection in some regions. The proportion of unexplained stillbirth varies widely across reported studies. The causes of neonatal deaths have been more consistently reported and are largely due to complications of preterm birth, intrapartum-related events, and infections. Intrapartum factors have been reported as causal in 40 % of perinatal deaths in low-income country settings. Women living in disadvantage have much higher rates of stillbirths and neonatal deaths than their counterparts. Clinical audits consistently show that a high proportion of perinatal deaths are potentially avoidable.

 Conclusions: Stillbirth and neonatal death rates are widely used as an indicator of the health of communities and the quality and safety of obstetric and newborn care. While low- and middle-income countries bear the majority of the burden, slow progress in reducing neonatal deaths and, more prominently, stillbirths is a worldwide problem. Improvements in the living standards for disadvantaged women, including education and employment opportunities and access to quality care, are imperative to address the disparity in outcomes across all settings. Epidemiological methods applied to perinatal data can assist in understanding where to focus attention. However, the paucity of high-quality data limits such analyses, posing a significant challenge to prevention of perinatal deaths. More effective data systems are needed, including a global classification system.