NCC EFM EXAM Extra 470+ Practice Questions and
Answers
Polyhydramnios - ANSWER single MVP > 8 cm or AFI >24; 1% of pregnancies;
60% idiopathic; multiple gestation, maternal diabetes, hydrops, anomalies, TORCH;
ass'd with cardiac/GI issues/renal issues
Oligohydramnios - ANSWER single MVP < 2 cm or AFI < 5 at term (less than
5%ile); associated with FGR, placental abnormalities, urinary tract abnormalities,
post-term pregnancies, ruptured or idiopathic membranes
Doppler - ANSWER US transducer, depicts valve closure; uses autocorrelation
Autocorrelation - ANSWER successive US waveforms at many points; current
technology which is more accurate at detecting FHR variability; controls artifact
sound waves
Toco/tocotransducer - ANSWER detects change in contour with contractions; place
at fundus or at area of maximum palpation; difficult to measure with obesity,
polyhydramnios
Fetal scalp electrode measures - ANSWER R-R waves; still has issues with artifact;
risk of injury, measuring maternal HR in instance of fetal demise; rupture and dilation
required
IUPC - ANSWER solid>fluid filled tips, measures mmHg and allows amnioinfusion;
issue with displacement, perforation, placental abruption
Intermittent auscultation - ANSWER goal is baseline 110-160, +/-accels, no decels;
if present, put on continuous monitor min 20 minutes); cannot determine variability or
types of FHR decels
Active phase auscultation - ANSWER q15 min for high risk up to q30min
Second stage auscultation - ANSWER q5 min if high risk up to q15min
Fetal tolerance of labor - ANSWER auscultate after a contraction x 30-60 seconds;
document rate, rhythm, accels, decels
Doppler vs. fetoscope - ANSWER doppler uses autocorrelation and detects valve
closure; fetoscope listens through opening in heart wall?
Signal ambiguity - ANSWER confusing maternal and fetal heart rate; common with
repositioning, fetal movement, during pushing (maternal tachycardia); can occur
even with fetal demise due to FSE recording maternal blood flow through the
placenta
, Suspect signal ambiguity - ANSWER when there is lower baseline or >50%
contractions with accelerations (especially with pushing); verify and document
maternal heart rate via pulse oximetry
Halving/doubling - ANSWER Halving occurs if FHR >180-200; may double if rate
<50
Extrinsic factors - ANSWER maternal oxygenation, uterine blood flow, placenta
exchange, umbilical blood flow; intrinsic factors = fetal circulation, oxygenation of
tissues, FHR regulation
Primary source of oxygen for the feus - ANSWER the maternal respiratory system
Uterine blood flow - ANSWER 60ml/min non-pregnant vs. 500-1000ml/min; 10-15%
maternal cardiac output
Normal blood flow pathway - ANSWER Blood from maternal vein > intervillous pool
of maternal blood > umbilical vein (oxygenated blood)
Normal placenta - ANSWER Placenta has 15-20 lobules on maternal surface;
Decreased surface area of chorionic villi from abnormal development, infection,
thrombosis, hemorrhage, inflammation (chorio increases risk of CP), degenerative
changes with increasing gestational age (calcifications)/HTN/DM - can cause IUGR,
hypoxia, FHR decels
Acute drop in placental function - ANSWER fetal asphyxia
Chronic drop in placental function - ANSWER FGR
O2 and CO2 - ANSWER simple transport (diffusion); electrolytes, fat soluble
vitamins, narcotics, anesthetic gasses, antibiotics
Glucose - ANSWER facilitated transport, by carrier molecules
Active - ANSWER amino acids, calcium, iron, water soluble vitamins (uses ATP)
Umbilical blood flow - ANSWER 2 arteries (deoxygenated) and 1 vein (oxygenation)
Fetal circulation - ANSWER when compromised, fetal blood redistributed to heart,
brain, adrenals; shunting and FHR increase compensate for decreased blood flow
and hypoxemia; limit mixing of oxygenated and deoxygenated blood
Fetal hemoglobin - ANSWER AND increased O2 affinity > adult; fetus has
increased cardiac output and heart rate
Ductus venosus - ANSWER (highest oxygenation) > ductus arteriosus (least
oxygenation);
Answers
Polyhydramnios - ANSWER single MVP > 8 cm or AFI >24; 1% of pregnancies;
60% idiopathic; multiple gestation, maternal diabetes, hydrops, anomalies, TORCH;
ass'd with cardiac/GI issues/renal issues
Oligohydramnios - ANSWER single MVP < 2 cm or AFI < 5 at term (less than
5%ile); associated with FGR, placental abnormalities, urinary tract abnormalities,
post-term pregnancies, ruptured or idiopathic membranes
Doppler - ANSWER US transducer, depicts valve closure; uses autocorrelation
Autocorrelation - ANSWER successive US waveforms at many points; current
technology which is more accurate at detecting FHR variability; controls artifact
sound waves
Toco/tocotransducer - ANSWER detects change in contour with contractions; place
at fundus or at area of maximum palpation; difficult to measure with obesity,
polyhydramnios
Fetal scalp electrode measures - ANSWER R-R waves; still has issues with artifact;
risk of injury, measuring maternal HR in instance of fetal demise; rupture and dilation
required
IUPC - ANSWER solid>fluid filled tips, measures mmHg and allows amnioinfusion;
issue with displacement, perforation, placental abruption
Intermittent auscultation - ANSWER goal is baseline 110-160, +/-accels, no decels;
if present, put on continuous monitor min 20 minutes); cannot determine variability or
types of FHR decels
Active phase auscultation - ANSWER q15 min for high risk up to q30min
Second stage auscultation - ANSWER q5 min if high risk up to q15min
Fetal tolerance of labor - ANSWER auscultate after a contraction x 30-60 seconds;
document rate, rhythm, accels, decels
Doppler vs. fetoscope - ANSWER doppler uses autocorrelation and detects valve
closure; fetoscope listens through opening in heart wall?
Signal ambiguity - ANSWER confusing maternal and fetal heart rate; common with
repositioning, fetal movement, during pushing (maternal tachycardia); can occur
even with fetal demise due to FSE recording maternal blood flow through the
placenta
, Suspect signal ambiguity - ANSWER when there is lower baseline or >50%
contractions with accelerations (especially with pushing); verify and document
maternal heart rate via pulse oximetry
Halving/doubling - ANSWER Halving occurs if FHR >180-200; may double if rate
<50
Extrinsic factors - ANSWER maternal oxygenation, uterine blood flow, placenta
exchange, umbilical blood flow; intrinsic factors = fetal circulation, oxygenation of
tissues, FHR regulation
Primary source of oxygen for the feus - ANSWER the maternal respiratory system
Uterine blood flow - ANSWER 60ml/min non-pregnant vs. 500-1000ml/min; 10-15%
maternal cardiac output
Normal blood flow pathway - ANSWER Blood from maternal vein > intervillous pool
of maternal blood > umbilical vein (oxygenated blood)
Normal placenta - ANSWER Placenta has 15-20 lobules on maternal surface;
Decreased surface area of chorionic villi from abnormal development, infection,
thrombosis, hemorrhage, inflammation (chorio increases risk of CP), degenerative
changes with increasing gestational age (calcifications)/HTN/DM - can cause IUGR,
hypoxia, FHR decels
Acute drop in placental function - ANSWER fetal asphyxia
Chronic drop in placental function - ANSWER FGR
O2 and CO2 - ANSWER simple transport (diffusion); electrolytes, fat soluble
vitamins, narcotics, anesthetic gasses, antibiotics
Glucose - ANSWER facilitated transport, by carrier molecules
Active - ANSWER amino acids, calcium, iron, water soluble vitamins (uses ATP)
Umbilical blood flow - ANSWER 2 arteries (deoxygenated) and 1 vein (oxygenation)
Fetal circulation - ANSWER when compromised, fetal blood redistributed to heart,
brain, adrenals; shunting and FHR increase compensate for decreased blood flow
and hypoxemia; limit mixing of oxygenated and deoxygenated blood
Fetal hemoglobin - ANSWER AND increased O2 affinity > adult; fetus has
increased cardiac output and heart rate
Ductus venosus - ANSWER (highest oxygenation) > ductus arteriosus (least
oxygenation);
