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Dawes-Redman Antepartum Analysis
11.3 The Dawes-Redman Criteria
• An episode of high variation, above the fi rst centile for gestational age.
• No decelerations > 20 lost beats ( >100 lost beats on records longer than
30 minutes).
• Basal heart rate between 116 and 160 bpm, though a slightly lower or
higher rate may be acceptable after 30 minutes, if all other parameters is
normal. An asterisk on the analysis shows that the fetal heart rate is low or
high, but that in the context of the rest of the record, it is acceptable.
• At least one fetal movement * or three accelerations.
• No evidence of a sinusoidal fetal heart rate rhythm.
• Short-term variation should be 3 ms or greater.
• Either an acceleration
Or variability in high episodes > the tenth centile and fetal movements > 20.
• No errors or decelerations at the end of the record.
* The analysis only uses maternally sensed movement
11.4 Dawes-Redman Analysis
Note: Dawes-Redman analysis is ON by default on Antepartum
monitors (Team 3A).
Analysis is performed at 10 minutes, and every 2 minutes thereafter up to a
maximum of 60 minutes. The analysis fi ts a baseline to the fetal heart rate data
collected so far, and from this measures accelerations and decelerations. Short-
term variation is calculated, and episodes of high and low variation looked for.
The analysis can be stopped once the criteria have been met. Team 3 produces
a report of the analysis results at the end of the trace. Abnormalities are
highlighted. If the analysis is not stopped, it is possible for the results to change
to CRITERIA NOT MET. As more data is received, a subsequent analysis may
re-fi t the baseline so that, for example, an episode of high variation is no longer
above the fi rst centile.
Twin and Triplet traces
Dawes-Redman analysis does not take account of fetal movement when
analysing twins.
Dawes-Redman analysis cannot be used when monitoring triplets.
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