Fetal ST Segment and T Wave Analysis in Labor

A Randomized Trial of Fetal ECG ST Segment and T Wave Analysis as an Adjunct to Electronic
Fetal Heart Rate Monitoring (STAN):

Fetal ECG analysis of the ST segment (STAN) is now FDA-approved and clinically available in
the United States as an adjunct for the interpretation of electronic fetal heart rate
patterns. There have been a number of randomized controlled trials as well as observational
studies in Europe documenting utility of this modality in terms of reducing fetal acidosis at
birth, and decreasing the need for operative vaginal delivery. However, despite these
endorsements, there remain concerns with the application of the technology to the United
States. None of the randomized trials were performed in the United States where patient
case-mix and obstetrical practice, such as the use of fetal scalp pH, differ from Europe,
which may affect the impact of this technology on perinatal outcomes. Moreover, the results
of the European studies are not uniformly positive.

This protocol describes a randomized controlled trial of the STAN technology as an adjunct to
electronic fetal heart rate monitoring versus fetal heart rate monitoring alone.

Inclusion Criteria:

- Singleton, cephalic pregnancy

- Gestational age at least 36 weeks, 1 day

- Cervical dilation of at least 2 cm and no more than 7 cm

- Ruptured membranes

Exclusion Criteria:

- Multifetal gestation

- Planned cesarean delivery

- Need for immediate delivery

- Absent variability or sinusoidal pattern at any time, or a Category II fetal heart
rate pattern with absent variability in the last 20 minutes before randomization

- Inability to obtain or maintain an adequate signal within 3 trials of electrode
placements

- Occurrence of any ST event during attempt to obtain adequate signal

- Patient pushing in the first stage of labor

- Known major fetal anomaly or fetal demise

- Previous uterine surgery

- Placenta previa on admission

- Maternal fever greater than or equal to 38 C or 100.4 F

- Active HSV infection

- Known HIV or hepatitis infection

- Other maternal and fetal contraindications for using the STAN monitor

- Enrollment in another labor study

- Participation in this trial in a previous pregnancy

- No certified or authorized provider available