Abstract
Fetal death diagnosed after 20 weeks of gestation occurs in 6/1000 births and accounts for more than one-half of annual infant deaths in the United States.1 More than 80% of fetal deaths occur prior to the onset of labor.2-5 Since birthweight has been considered as a surrogate of fetal growth, and a small-forgestational-age (SGA) neonate was associated with fetal death,6-10 fetal growth restriction (FGR) is frequently cited as a precedent of antepartum stillbirth.7, 11-14 The relationship between fetal growth and stillbirth is poorly understood for several reasons. First, the exact time of death is unknown and an overestimation of the gestational age leads to increased frequency of SGA among stillbirths.6, 10, 14-18 Second, although, most cases of FGR and fetal overgrowth result in a live birth,11, 19-21 abnormal fetal growth may still be a cause of fetal death.6, 10, 14, 15, 22-24 Third, it is unclear whether impaired fetal growth is a cause of fetal death2 or is a result of placental dysfunction.
Fourth, maternal characteristics affecting growth of normal live-born neonates are also risk factors for stillbirth.25 Finally, given that most reports examine maternal-fetal conditions present at the time of or after fetal death, longitudinal studies are needed to gain insight into causality.7, 19, 26-29 Although improvement in prediction of SGA at birth by serial ultrasound examinations compared to a single last available biometry is controversial,30-32 the assessment of fetal growth velocity has been proposed to improve the detection of growth-restricted fetuses at increased risk of adverse perinatal outcome.33-36.