COMPUTERIZED ANALYSIS OF FETAL HEART-RATE RECORDINGS IN PATIENTS WITHDIABETES-MELLITUS - THE DAWES-REDMAN CRITERIA MAY NOT BE VALID INDICATORS OF FETAL WELL-BEING

Computerised cardiotocograph analysis has been used in our medical ant enatal clinic for women with insulin dependent diabetes mellitus for f ive years. We had observed that many of the patients failed the comput er criteria and wished to examine this finding in more detail. All car diotocographs from 40 pregnant women with insulin dependent diabetes m ellitus who delivered between 1992 and 1995 were reviewed. The number of traces failing the criteria were calculated. Outcome was compared b etween patients with a normal trace and those with an abnormal trace. 233 recordings were examined. 30.5 % of antenatal CTGs failed the crit eria because of absent high episodes of variation (a parameter which i s a specific marker of fetal well-bring). After excluding repeat trace s on all patients a sample of 26 traces was examined. 34.6 % of these had failed because of absent high episodes of variation. Both these fi gures are significantly higher than the published normal values. There was no apparent difference in neonatal outcome between women whose tr ace had failed (9) and those with a normal trace (17). We suggest that the normal values of criteria used to analyse computerised CTGs may n ot be valid when applied to fetuses of women with diabetes mellitus.