Tachysystole - ANSWER Any excessive uterine activity (UA); >5 contractions in a 10
minute window, averaged over 30 mins.
Repetitive Decelerations - ANSWER 3 or more decels in a row
Recurrent Decelerations - ANSWER Decels that occur with >50% of contractions in a
20 minute period
Intermittent Decelerations - ANSWER Decels that occur with <50% of contractions in a
20 minute period
Gradual Deceleration - ANSWER ≥30 seconds from onset to nadir
Episodic Gradual Deceleration - ANSWER A gradual decel NOT associated with a
contraction
Interpretable Electronic Fetal Monitoring - ANSWER Electronic fetal monitoring tracing
that has a continuous display of the fetal heart rate and uterine activity with minimal gaps.
Uterine Activity - How is this documented? - ANSWER Number of contractions present
in a 10-minute window, averaged over 30 minutes (e.g. 3 contractions in 10 minutes) -
UNLESS atypical/abnormal in the first 10 minutes of tachysystole - initiate a response
without averaging over 30 minutes
1
,Recommended (minimum) tracing for EFM - ANSWER 20 Minutes
Early Deceleration - ANSWER *safe*. Begin prior to peak of the contraction and end by
the end of it. Caused by head compression (E.G associated with fetal descent in the pelvis /
full dilation). No need for intervention if variability is within normal range and the FHR is
within normal range. Characteristic of nadir occurring at same time as peak of contraction.
*Usually symmetrical*. Return to normal by end of contraction.
**Early decelerations are said to be a mirror image of the contractions.**
Uncomplicated variable deceleration - ANSWER Caused by cord compression. 15 BPM
below baseline lasting >15s. Often have shoulders (initial accel, followed by rapid decel to
the nadir, rapid return to baseline, followed by secondary brief accel). Common in late 1st
stage.
*NORMAL* if occasional uncomplicated variable decelerations occur
*ATYPICAL* if repetitive (greater than or equal to 3) uncomplicated variable decelerations
occur
Complicated Variable Deceleration - ANSWER *Not ok - May be indicative of fetal
hypoxia / acidemia* Also caused by cord compression, but does not return to baseline by
end of contraction. Any of: May last >60s AND go down to <60BPM OR decrease by >60BPM
below baseline; overshoot of 20BPM X 20secs after decel; variable decel in presence of
minimal or absent baseline variability, OR baseline tachycardia/ bradycardia. Can occur in 1st
or 2nd stage.
Late decelerations - ANSWER *Also not ok - indicates uteroplacental insufficiency, or
decreased uteroplacental blood flow during contraction / associated with fetal hypoxia and
acidemia* . = lowered fetal pO2.
Symmetrical - gradual drop and return to baseline, but unlike early decels, the onset, nadir
and recovery occurs AFTER the peak of the contraction.
2
, **Gradual, smooth, delayed deceleration**
IA during 1st stage - how often? - ANSWER q15 mins
IA during 2nd stage - how often? - ANSWER q5 mins
EFM During 2nd stage - interpret how often? - ANSWER At least q15mins, otherwise
q5mins
Spontaneous Accelerations - ANSWER *Good* - Reassuring, but not required to
classify EFM as 'normal'.
Recommended in Response to atypical EFM and abnormal IA - ANSWER Digital Fetal
Scalp Stimulation
Primary factors that regulate the FHR - ANSWER The medulla oblongata (in the
brainstem), the autonomic nervous system, baroreceptors, and chemoreceptors
Secondary factors that regulate the FHR - ANSWER Humoral or endocrine factors,
blood composition and volume, blood vessel diameter, cardiac contractility and amniotic
fluid composition, as well as substances released from the: hypothalamus, pituitary gland,
adrenal glands, adipose tissue, pancreas, kidneys, intestines, liver, spleen, bone marrow and
heart
CNS - Medulla Oblongata... - ANSWER Serves as the integrative centre for central and
peripheral neural control of the cardiovascular and respiratory system. Blood pressure, heart
rate, and vascular resistance are controlled at this level.
3
minute window, averaged over 30 mins.
Repetitive Decelerations - ANSWER 3 or more decels in a row
Recurrent Decelerations - ANSWER Decels that occur with >50% of contractions in a
20 minute period
Intermittent Decelerations - ANSWER Decels that occur with <50% of contractions in a
20 minute period
Gradual Deceleration - ANSWER ≥30 seconds from onset to nadir
Episodic Gradual Deceleration - ANSWER A gradual decel NOT associated with a
contraction
Interpretable Electronic Fetal Monitoring - ANSWER Electronic fetal monitoring tracing
that has a continuous display of the fetal heart rate and uterine activity with minimal gaps.
Uterine Activity - How is this documented? - ANSWER Number of contractions present
in a 10-minute window, averaged over 30 minutes (e.g. 3 contractions in 10 minutes) -
UNLESS atypical/abnormal in the first 10 minutes of tachysystole - initiate a response
without averaging over 30 minutes
1
,Recommended (minimum) tracing for EFM - ANSWER 20 Minutes
Early Deceleration - ANSWER *safe*. Begin prior to peak of the contraction and end by
the end of it. Caused by head compression (E.G associated with fetal descent in the pelvis /
full dilation). No need for intervention if variability is within normal range and the FHR is
within normal range. Characteristic of nadir occurring at same time as peak of contraction.
*Usually symmetrical*. Return to normal by end of contraction.
**Early decelerations are said to be a mirror image of the contractions.**
Uncomplicated variable deceleration - ANSWER Caused by cord compression. 15 BPM
below baseline lasting >15s. Often have shoulders (initial accel, followed by rapid decel to
the nadir, rapid return to baseline, followed by secondary brief accel). Common in late 1st
stage.
*NORMAL* if occasional uncomplicated variable decelerations occur
*ATYPICAL* if repetitive (greater than or equal to 3) uncomplicated variable decelerations
occur
Complicated Variable Deceleration - ANSWER *Not ok - May be indicative of fetal
hypoxia / acidemia* Also caused by cord compression, but does not return to baseline by
end of contraction. Any of: May last >60s AND go down to <60BPM OR decrease by >60BPM
below baseline; overshoot of 20BPM X 20secs after decel; variable decel in presence of
minimal or absent baseline variability, OR baseline tachycardia/ bradycardia. Can occur in 1st
or 2nd stage.
Late decelerations - ANSWER *Also not ok - indicates uteroplacental insufficiency, or
decreased uteroplacental blood flow during contraction / associated with fetal hypoxia and
acidemia* . = lowered fetal pO2.
Symmetrical - gradual drop and return to baseline, but unlike early decels, the onset, nadir
and recovery occurs AFTER the peak of the contraction.
2
, **Gradual, smooth, delayed deceleration**
IA during 1st stage - how often? - ANSWER q15 mins
IA during 2nd stage - how often? - ANSWER q5 mins
EFM During 2nd stage - interpret how often? - ANSWER At least q15mins, otherwise
q5mins
Spontaneous Accelerations - ANSWER *Good* - Reassuring, but not required to
classify EFM as 'normal'.
Recommended in Response to atypical EFM and abnormal IA - ANSWER Digital Fetal
Scalp Stimulation
Primary factors that regulate the FHR - ANSWER The medulla oblongata (in the
brainstem), the autonomic nervous system, baroreceptors, and chemoreceptors
Secondary factors that regulate the FHR - ANSWER Humoral or endocrine factors,
blood composition and volume, blood vessel diameter, cardiac contractility and amniotic
fluid composition, as well as substances released from the: hypothalamus, pituitary gland,
adrenal glands, adipose tissue, pancreas, kidneys, intestines, liver, spleen, bone marrow and
heart
CNS - Medulla Oblongata... - ANSWER Serves as the integrative centre for central and
peripheral neural control of the cardiovascular and respiratory system. Blood pressure, heart
rate, and vascular resistance are controlled at this level.
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