Initial maternal awareness of fetal movement typically occurs at 16-20 weeks gestation, and maternal monitoring of fetal movement
(eg, kick counts) begins in the third trimester (�28 weeks gestation). Monitoring of fetal movement is a simple method for evaluating
fetal activity (eg, tone, limb extension and flexion) because normal fetal activity typically indicates a normal fetal acid-base status and
low risk of fetal demise. In contrast, hypoxemic or acidemic fetuses have reduced fetal activity as a compensatory mechanism to
divert blood flow from peripheral tissues to preserve oxygen for the CNS. Therefore, maternal sensation of decreased fetal
movement requires further evaluation of fetal status (Choice D)
The best next step in patients with decreased fetal movement is a nonstress test (NST), a noninvasive method of tracking fetal
heart rates over time (eg, 20-40 minutes)
• Reactive NSTs (eg, �2 accelerations, baseline 110-160/min, moderate variability) are consistent with a normal fetal acid-base
status.
• Nonreactive NSTs (eg, <2 accelerations) may indicate fetal hypoxemia and acidemia. Additional antepartum testing (eg,
biophysical profile) is indicated in these patients
(Choice A) An amniotic fluid index is performed in patients with decreased fetal movement if the NST is nonreactive or if fetal
decelerations are present to evaluate for oligohydramnios, which may indicate chronic uteroplacental insufficiency and impending fetal
compromise
(Choice 8) Induction of labor is indicated in patients at term (;,,39 weeks) gestation with persistent decreased fetal movement due to
the risk of unexplained stillbirth in these patients. It can also be performed at earlier gestation if significant signs of fetal distress (eg,
late fetal decelerations) or maternal deterioration are present
(Choice E) Umbilical artery Doppler ultrasound is used to monitor fetal status in pregnancies complicated by maternal hypertension
or fetal growth restriction. It is not used in the evaluation of decreased fetal movement
Educational objective:
The maternal sensation of decreased fetal movement may be due to fetal hypoxemia or acidemia and is concerning for increased risk
of demise. Patients with decreased fetal movement require further investigation of fetal status with nonstress testing.
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