Clinical significance of sinusoidal fetal heart rate pattern

Sinusoidal fetal heart rate pattern has been regarded as a sign of fetal jeopardy and 92 instances of this pattern were analysed. The morphologically different major and minor sinusoidal patterns were assessed with regard to their clinical significance as predictors of fetal compromise. There were 83 instances of minor sinusoidal pattern (amplitude of oscillation less than 25 beats/min) with only one antepartum fetal death. Major sinusoidal pattern (amplitude of oscillation greater than 25 beats/min) was diagnosed in nine patients and in six of them the fetus died before, during or after delivery. It is concluded that patients with minor sinusoidal heart rate patterns may be managed expectantly, whereas on the rare occasion when a major sinusoidal pattern is seen expeditious delivery is justified.