The Heightened Significance of Prolonged Bradycardia Associated with Intrauterine Growth Retardation

ABSTRACT

The significance and management of prepartum bradycardia is not well established in prepartum fetal assessment. The incidence of prolonged bradycardia was 3.5% (45 per 1284), defined as a decrease of ≥ 40 beats per minute of the fetal heart rate (FHR) below the baseline for at least 2 minutes. Thirty-two maternal, fetal, and FHR tracing characteristics were examined to study correlations between the variables, the presence of the bradycardia, and neonatal outcome. Neonatal outcome was evaluated by dividing the population into two groups. Group 1 consisted of infants with 1-minute Apgar scores < 6 and NICU admissions > 24 hours. Group 2 comprised infants with 1-minute Apgar scores > 6 and no NICU admission or < 24 hours NICU admission. IUGR was diagnosed in 40% of the patients. Statistically significant associations were found for correlations between Group 1 infants and IUGR (P < .05), oligohydramnios (P < .05), cesarean section rate (P < .04), and the presence of meconium (P < .01). mere were no fetal heart rate characteristics found to be significantly associated with IUGR or neonatal outcome. The data do not support the need for immediate delivery in patients with prolonged prepartum bradycardia, but its presence does warrant a workup for intrauterine growth retardation.