Intravenous Pitocin therapy

“A primigravida at 43 weeks gestation was admitted for labor induction by intravenous Pitocin therapy three hours ago. On observation on the external monitor tracing, the nurse notes that with the last two contractions, the fetal heart rate decreased after the contraction peak and returned to baseline after the contraction ended. A decrease in variability is also noted. What is the pattern identified by the nurse and the possible reasons responsible for it? What actions should the nurse take?”