Saltatory fetal heart rate pattern.

A retrospective descriptive study reviewed 433 consecutive intrapartum fetal heart tracings. The saltatory fetal heart rate pattern was defined as fetal heart amplitude changes of greater than 25 beats per minute with an oscillatory frequency of greater than 6 per minute for a minimum duration of 1 minute. Data were analyzed for each mother-infant pair over the time of labor and birth. The saltatory pattern was demonstrated in 10 of the 433 tracings reviewed for an overall incidence of 2.3%. All 10 fetuses demonstrating the saltatory pattern were term (38 to 42 weeks' gestation). None of the 147 preterm fetuses demonstrated the saltatory pattern (P less than .02). In 6 patients the saltatory pattern was observed after parenteral ephedrine administration, in 3 patients with uterine hyperstimulation, and in 1 patient during cervical examination. When the saltatory pattern was seen with ephedrine administration, it was present only at total doses of greater than or equal to 30 mg (P less than .001). In all patients the saltatory pattern occurred during active phase or second stage of labor. Short-term and long-term variability recorded by the fetal-scalp electrode were present both before and after the episode of saltatory pattern. At birth, all 10 infants were vigorous, with Apgar scores of 8/9 or 9/9. In the absence of abnormal periodic fetal heart rate changes and with the presence of short-term and long-term variability, the saltatory fetal heart rate pattern appears benign.