Obstetricians and Gynecologists
WOMEN’S HEALTH CARE PHYSICIANS
P RACTICE BULLET IN clinical management guidelines for obstetrician – gynecologists
Number 145, July 2014
(Replaces Practice Bulletin Number 9, October 1999)
Antepartum Fetal Surveillance
The goal of antepartum fetal surveillance is to prevent fetal death. Antepartum fetal surveillance techniques based on assessment of fetal heart rate (FHR) patterns have been in clinical use for almost four decades and are used along with real-time ultrasonography and umbilical artery Doppler velocimetry to evaluate fetal well-being. Antepartum fetal surveillance techniques are routinely used to assess the risk of fetal death in pregnancies complicated by preexisting maternal conditions (eg, diabetes mellitus) as well as those in which complications have developed (eg, fetal growth restriction). The purpose of this document is to provide a review of the current indications for and techniques of antepartum fetal surveillance and outline management guidelines for antepartum fetal surveillance that are consistent with the best scientific evidence.
Background
Physiology of Fetal Heart Response and
Fetal Behavioral State Alteration
In animals and humans, FHR pattern, level of activity, and degree of muscular tone are sensitive to hypoxemia and acidemia (1–4). Redistribution of fetal blood flow in response to hypoxemia may result in diminished renal perfusion and oligohydramnios (5). Surveillance techniques such as cardiotocography, real-time ultrasonography, and maternal perception of fetal movement can identify the fetus that may be undergoing some degree of uteroplacental compromise. Identification of suspected fetal compromise provides the opportunity to intervene before progressive metabolic acidosis results in fetal death. However, acute, catastrophic changes in fetal status, such as those that can occur with placental abruption or an umbilical cord accident, are generally not predicted
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