Evaluation of fetal heart rate patterns during the second stage of labor through fetal oximetry

The purpose of this study was to assess the feasibility and accuracy of fet al pulse oximetry during the second stage of labor in cases with abnormal f etal heart rate (FHR) patterns with reference to postpartum acid-base statu s and Apgar scores, Forty-eight parturients with normal and 20 parturients with abnormal FHR tracings du ring the second stage of labor were monitored by fetal pulse oximetry and postpartum umbilical artery pH, pO(2), pCO(2) values and 1- and 5-min Apgar scores, The mean SpO(2) value was 55.47 +/- 9 .95% in cases with normal and 52.55 +/- 16.42% in cases with abnormal FHR p atterns. A significant correlation was noted between fetal SpO(2) and umbil ical artery pH in cases with normal (r = 0.76, p < 0.05) as well as in case s with abnormal FHR patterns (r = 0.78, p < 0.05). No significant correlati on was found between fetal SpO(2) and Apgar scores at 1 and 5 min in cases with normal FHR patterns. On the contrary a significant correlation was not ed in cases with abnormal FHR patterns. A normal FHR pattern alone is reass uring, In cases with abnormal FHR, fetal pulse oximetry is an objective met hod for distinguishing a hypoxic fetus.