Comparison of Low-dose and High-dose Oxytocin Regimens for Labor Augmentation

This randomized double blind clinical trial of consenting nulliparous women in spontaneous labor who require oxytocin for labor augmentation seeks to determine whether use of a high dose oxytocin regimen improves obstetric outcomes when compared with a low dose oxytocin regimen, in a manner that is safe for both mother and neonate.

This project will include 1002 women recruited from the obstetrical service at Prentice Women's Hospital. Women will be included if they are at least 36 weeks gestation, have a singleton pregnancy, and have been diagnosed with spontaneous labor or spontaneous rupture of membranes. Women will be exposed to oxytocin for the indication of labor augmentation at the discretion of their obstetric provider.

Women will be randomized with equal probability to intervention group using a fixed allocation procedure. To maintain a double blind design, the Prentice Women's Hospital pharmacy will carry out the randomization of oxytocin solutions according to the random assignment so that neither the women or their care providers nor the investigators will know the identity of the intervention assignment. The low-dose oxytocin regimen group will receive a starting oxytocin regimen concentration rate of 2 milliunits/minute that can be increased at increments of 2 milliunits/minute, as per the discretion of their obstetric provider. The high-dose oxytocin regimen group will receive a starting oxytocin regimen concentration rate of 6 milliunits/minute that can be increased at increments of 6 milliunits/minute, as per the discretion of their obstetric provider.

Once the women are enrolled, randomized, and in receipt of their assigned interventions, further clinical management will be left to the discretion of each woman's obstetric provider.

Prior to discharge from the hospital, baseline demographic and clinical data will be obtained via chart review.

Inclusion criteria

• Able to give informed written consent
• Age 18-45 years
• Nulliparous
• Pregnant with a live singleton gestation that is equal to or greater than 36 weeks
• Diagnosed with at least 6 regular uterine contractions in an observation period of no more than 60 minutes and at least one of the following: spontaneous rupture of membranes, OR cervix greater than or equal to 3 centimeters dilated OR cervix at least 80% effaced.
• The participant's attending obstetric physician or midwife has determined that the participant needs administration of oxytocin infusion for labor augmentation. Labor augmentation will be defined as stimulation of uterine contractions when spontaneous contractions have failed to result in progressive cervical dilation of descent of fetus.

Exclusion criteria

• Women not meeting the above criteria
• History of prior cesarean section or uterine surgery
• Fetus in non-cephalic presentation
• Participant is undergoing labor induction (i.e. cervical ripening)
• Non-English speaking