The effect of cocaine on fetal heart rate tracing during labor
OBJECTIVE: To détermine the characteristics of fetal heart rate tracings during labor in women with recent cocaine use. STUDY DESIGN: Between 11/9;") and 2/96. 25 women were identified from the toxicology and delivery logs .is being positive for cocaine during labor. The next deliverv within one week at the same gestational age with a negative toxicology screen was chosen as a control. Twenty one pairs with complete 1'etal tracings and medical records were available for review. L'tili/ing the Lyons scoring system, each tracing was independent!) analyzed b\ a perinatologist blinded to the toxicology status of the woman. The tracing were graded on the following characteristics: baseline heart rate, short and lung term variability, presence of accelerations, and frequency. i\pe and severity of decelerations. Primaiv outcome variables e\aluated included Apgar score, birth weight, cord pH, and obstetric complications. Analysis was bv "t" test, X and Fisher exact test with significance at the 0.05 level! RESULTS: The median Lyons score for cocaine positive women was 7 versus a score of 8 for the controls, p ~ NS. And abnormal score (<8) was noted in 11 '21 (52%) tracings in the cocaine group and 8/'21 (38%) of the conttol group. There was no difference in cord pH or 5 minute Apgar for cocaine versus controls. CONCLUSIONS: Although, cocaine exposed fetuses have significant changes in the fetal heart rate tracing during labor, these changes may not be predictive of fetal distress.
