Chapter 21
Assessment of Fetal Well-Being
Resource Library
Prentice Hall Nursing Medialink DVD-ROM
Audio Glossary
NCLEX Review
Video: Through the Eyes of a Nurse—The Third Trimester
Companion Website
Additional NCLEX Review
Case Study: Client Undergoing Contraction Stress Test
Care Plan Activity:Monitoring Well-Being of a Slow-Developing Fetus
Applications: Fetal Assessment; Fetal Lung Maturity
Critical Thinking
Learning Objective 1
Describe the various psychologic responses to antenatal testing.
Concepts for Lecture
1. Psychologic Response to Testing
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Routine part of care
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Confirmation of viability
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Psychologic preparation for attachment
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Fear and anxiety
Learning Objective 2
Identify indications and interpret findings for ultrasound examinations performed in the first
trimester.
Concepts for Lecture
1. First Trimester Ultrasound
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Establish gestational age
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Crown to rump length
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Most accurate between 6 and 10 weeks
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Nuchal translucency testing
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Combined ultrasound and serum testing
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Risk for chromosomal disorder
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Screened between 11 weeks and 1 day and 16weeks and 7 days
Learning Objective 3
Describe the procedures used in the first trimester to confirm fetal viability.
Concepts for Lecture
1. First Trimester Viability Confirmation
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Serial quantitative serum beta hCG testing
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Progesterone
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Ultrasound
Learning Objective 4
Delineate the use of ultrasound in the second trimester to assess fetal life, number, presentation,
anatomy, age, and growth.
Concepts for Lecture
1. Second Trimester Ultrasound
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Fetal life
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Fetal number
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Fetal presentation
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Fetal anatomy
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Gestational age
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Amniotic fluid index
2. Second Trimester Ultrasound
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Placental position
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Uterus
Learning Objective 5
Compare the indications and procedures for fetal movement awareness, the nonstress test,
vibroacoustic stimulation, the contraction stress test, biophysical profile, and amniotic fluid
index.
Concepts for Lecture
1. Fetal Movement
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Noninvasive
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Cost-effective
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Indirect measure of the fetal central nervous system (CNS)
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Vigorous movement indicates fetal well-being
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Decreased movement is associated with chronic oxygen compromise
2. Nonstress Test (NST)
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Accelerations imply an intact CNS
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Acceleration patterns are affected by gestational age
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Accelerations must be 15 beats per minute above baseline, lasting 15
seconds
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Reactive—two or more accelerations within 20minutes
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Nonreactive—insufficient accelerations over 40minutes
3. Vibroacoustic Stimulation (VAS)
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Application of sound and vibration to stimulate fetal movement
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Used to facilitate NST
3. Contraction Stress Test (CST)
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Evaluates uteroplacental function
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Identifies intrauterine hypoxia
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Observes FHR response to contractions
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If compromised, FHR will decrease
3a Interpretation of CST
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Negative
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Positive
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Equivocal-suspicious
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Equivocal-hyperstimulatory
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Unsatisfactory
4 .Amniotic Fluid Index (AFI)
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Decreased uteroplacental perfusion results in oligohydramnios
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AFI of five or less requires further evaluation
5. Biophysical Profile (BPP)
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Fetal heart rate acceleration
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Fetal breathing
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Fetal movements
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Fetal tone
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Amniotic fluid volume
Learning Objective 6
Explain the purpose of maternal serum alpha-fetoprotein testing and the implications of
abnormal values.
Concepts for Lecture
1. Maternal Serum Alpha-Fetoprotein
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Component of quadruple check
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Screening test for
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Neural tube defects
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Trisomy 21 (Down syndrome)
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Trisomy 18
Performed between 15 and 22 weeks of gestation
Learning Objective 7
Contrast the use of amniocentesis and chorionic villus sampling in detecting a fetus with a
chromosomal disorder.
Concepts for Lecture
1. Amniocentesis (Figure 21.19)
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Used to detect genetic, metabolic, and DNA abnormalities
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Can detect neural tube defects
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Amniotic fluid obtained through needle aspiration
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Complications include
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Vaginal spotting and cramping
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Mild fluid leaking
2. Chorionic Villus Sampling (CVS)
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Used to detect genetic, metabolic, and DNA abnormalities
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Needle aspiration of chorionic villi from placenta
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Earlier diagnosis than amniocentesis
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Cannot detect neural tube defects
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Pregnancy loss is twice as high as with amniocentesis
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Potential for limb reduction
Learning Objective 8
Discuss fetal fibronectin and transvaginal measurement of cervical length as predictors of
preterm labor.
Concepts for Lecture
1. Predictors of Preterm Labor
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Fetal fibronectin (fFN)
°
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Presence between 20 and 34 weeks is predictor of preterm delivery
Cervical length and internal os
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Measured by ultrasound
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Shortened cervix and dilated internal os can predict preterm birth
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False-positive common
Learning Objective 9
Discuss how the lecithin/sphingomyelin ratio of the amniotic fluid and phosphatidylglycerol
(PG) can be used to assess fetal lung maturity.
Concepts for Lecture
1. Fetal Lung Maturity
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Lecithin/sphingomyelin ratio
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Ratio of 2 to 1 indicates fetal lung maturity
Phosphatidylglycerol (PG)
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Presence indicates fetal lung maturity