In the latter months of pregnancy, the disappearance of foetal movements usually directs the attention of the patient to the possibility of foetal death. The diagnosis of this condition, however, can be considered absolute only after repeated examinations, when one has failed to hear the foetal heart or perceive the movements of the child.
—J. Whitridge Williams (1903)
In Williams’ time, absolute documentation of fetal death was frustrating for both patient and obstetrician. Now, sonography provides prompt confirmation, which allows expedient induction of labor and delivery. However, epidemiologically, defining and reporting fetal deaths was—and continues to be—a challenge. In response, efforts to standardize the definition of stillbirth and analyze varying reports for application into clinical practice and public health policy are now being emphasized. Moreover, stillbirth research and prevention within the United States and abroad has expanded. Global public health efforts were stimulated in part by a six-part series in The Lancet. This compilation was considered a call to action after the recognition that an estimated 2.65 million stillbirths occur each year and that 98 percent of stillborn fetuses are from low- and middle-income countries (The Lancet’s Stillbirth Series Steering Committee, 2011a–f). Unfortunately, progress in improving these rates has been slow, as outlined in The Lancet’s subsequent five-part progress report, which emphasized the need for dedicated leadership, measured effects of interventions, and investigation into knowledge gaps (The Lancet’s Ending Preventable Stillbirths Series Study Group, 2016a–e).
In the United States, an estimated 1 million fetal losses are reported each year, and most occur before 20 weeks’ gestation. Fetal mortality data from the National Vital Statistics system are usually presented for fetal deaths after the 20-week threshold (MacDorman, 2015). Using this definition, numbers of fetal deaths in the United States in 2013 slightly surpassed numbers of infant deaths (Fig. 35-1). As shown in Figure 35-2, fetal death rates are highest at the earliest and latest gestational ages, which suggests etiological differences.
Percent distribution of fetal deaths at 20 weeks’ gestation or more and of infant deaths: United States, 2013. (Data from MacDorman MF, Reddy UM, Silver RM: Trends in stillbirth by gestational age in the United States, 2006–2012, Obstet Gynecol. 2015 Dec;126(6):1146–1150.)
Prospective fetal mortality rate per 1000 births by weeks of gestation: United States, 2013. (Redrawn from MacDorman MF, Reddy UM, Silver RM: Trends in stillbirth by gestational age in the United States, 2006–2012, Obstet Gynecol. 2015 Dec;126(6):1146–1150.)
DEFINITION OF FETAL MORTALITY
The current definition of fetal death adopted by the Centers for Disease Control and Prevention National Center for Health Statistics is based on a definition recommended by the World Health Organization (MacDorman, 2015...