Selection criteria for antenatal cardiotocography.

The present report considers two questions: 1) Which patients should be monitored routinely and 2) the interpretation of antenatal cardiotocography. During 26 months 812 patients with risk pregnancies were monitored with antenatal CTG. Most of them were daily registered. One hundred and seventeen (14.5%) showed pathological CTG changes. The CTG patterns were put into four classes according to the degree of seriousness. A comparison between high risk and low risk pregnancies showed that nearly all abnormal CTGs occurred in the high risk group. Within the high risk group, patients with essential hypertension and intrauterine growth retardation had pathological CTG changes in 20--30%. The study shows that high risk pregnancies should be monitored regularly at short intervals to allow early diagnosis of fetal distress. The value of routine CTG in low risk pregnancy can be questioned.