Monitoring of uterine activity in cases of labor augmentation, and newborn outcome

Objectives To examine whether internal tocography results in a better obstetric outcome than external tocography in cases where labor is augmented with oxytocin infusion. Methods In 127 nulliparous women who were delivered in our clinic, labor was augmented with oxytocin infusion due to slow progress. The patients were randomly selected (every second case) to be monitored by either external or internal tocography. Results The two groups of patients had similar cervical dilatation (4.0 +/- 0.7 cm vs. 4.0 +/- 0.8 cm) when oxytocin infusion was started and the mean total and maximum oxytocin doses were also similar (maximum dose 10.2 +/- 6 vs. 11.1 +/- 7 mU/min; mean total dose 2.1 +/- 0.4 vs. 2.2 +/- 0.6 IU). There was no statistical difference in cases where oxytocin was reduced due to hyperstimulation (10.4% vs. 8.33%) or difference in length of labor (236 +/- 87 vs. 240 +/- 92 min), uterine activity integral units (1820 +/- 289 vs. 1910 +/- 322), mode of delivery (normal delivery 82.1% vs. 78.3%; vacuum 10.4% vs. 11.7%, Cesarean section 7.5% vs. 10.0%) and obstetric outcome between the groups. Neonatal status, as assessed by 5-min Apgar scores and umbilical vein pH was similar in both groups. No assisted ventilation or admission to the neonatal intensive care unit was needed. The mean birth weight was also similar in both groups (3.5 +/- 0.4 vs. 3.4 +/- 0.6 kg). Conclusions Both groups of parturients were adequately monitored by both methods. We found no apparent advantages of internal over external tocography. There were no differences in mode of delivery as well as in newborn status.