Early Versus Delayed Oxytocin Infusion Following Amniotomy in Nulliparous Women

Sponsor

National University of Malaysia (Other)

Overall Status

Completed

CT.gov ID

NCT04200599

Collaborator

(none)

250

Enrollment

Arms

Actual Duration (Months)

Study Details

Study Description

Brief Summary

In UKM Medical Centre (UKMMC), delayed oxytocin augmentation at two hours following amniotomy is the routine obstetric practice in spontaneous or induced labour with intact membranes. This practice may potentially cause prolonged labour, extended labour room occupancy and increased maternal exhaustion while no additional benefit can be gained. On the other hand, recommendation for early oxytocin augmentation poses a dilemma as the effectiveness and safety of this practice are still in doubt.

Given this background, the aim of this study was to compare the effect of early versus delay oxytocin infusion in achieving successful vaginal delivery among the low-risk nulliparous women in UKMMC. Besides, this study also compares the adverse maternal and neonatal outcomes between the two practices.

Condition or Disease	Intervention/Treatment	Phase
Delivery Delayed Mode of Delivery Post Partum Hemorrhage Uterine Hyperstimulation	Other: duration of initiation of oxytocin	N/A

Detailed Description

This was a randomised controlled trial undertaken in the labour room of UKMMC for a period of eighteen months from August 2014 until February 2016. Eligible women who were admitted in spontaneous labour or for induction of labour were recruited. For women who underwent induction of labour, an interval of at least six hours following vaginal prostaglandin before recruitment was mandatory to avoid overlapping effect of prostaglandin and oxytocin. Upon enrolment, each patient was given a study explanation and written consent was obtained.

The randomisation sequence, either to the early oxytocin group or the delayed oxytocin group, was generated using the computer randomisation program in block of two. Allocation to either arm of treatment was determined by the sequential opening of sealed numbered envelopes.

In the first arm of early oxytocin group, labour augmentation with oxytocin was started early following artificial ruptured of membrane(ARM). In the second arm of delayed oxytocin group, oxytocin augmentation was delayed at two hours after ARM and this practice is currently being used as standard protocol in this hospital to manage women in labour. In both arms,the infusion rate was doubled every 30 minutes to a maximum of 48 mL/h or until four to five moderate contractions per 10 minutes were achieved at which point the infusion rate was maintained. Continuous fetal heart rate monitoring was maintained throughout the intrapartum period. Vaginal examination was performed at four hours after ARM as well as when clinically indicated ie. abnormal cardiotocography (CTG) and maternal desire to bear down. In the presence of abnormal CTG, either fetal blood sampling or expedited delivery was undertaken as per decided by the obstetrician in charge.

Study Design

Study Type:

Interventional

Actual Enrollment :

250 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Single (Participant)

Primary Purpose:

Treatment

Official Title:

Amniotomy and Early Oxytocin Infusion Versus Amniotomy and Delayed Oxytocin Infusion in Nulliparous Women: a Randomised Controlled Trial

Actual Study Start Date :

Aug 1, 2014

Actual Primary Completion Date :

Jan 30, 2016

Actual Study Completion Date :

Mar 31, 2016

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Early oxytocin Infusion labour augmentation with oxytocin was started early following amniotomy.	Other: duration of initiation of oxytocin mode of delivery
Active Comparator: Late oxytocin infusion oxytocin augmentation was delayed at two hours after amniotomny and this practice is currently being used as standard protocol in this hospital to manage women in labour.	Other: duration of initiation of oxytocin mode of delivery

Arm

Intervention/Treatment

Experimental: Early oxytocin Infusion

labour augmentation with oxytocin was started early following amniotomy.

Other: duration of initiation of oxytocin

mode of delivery

Active Comparator: Late oxytocin infusion

oxytocin augmentation was delayed at two hours after amniotomny and this practice is currently being used as standard protocol in this hospital to manage women in labour.

Other: duration of initiation of oxytocin

mode of delivery

Outcome Measures

Primary Outcome Measures

Achieving vaginal delivery [through study completion, an average of 18 months]
number of normal vaginal delivery
Neonatal outcome [through study completion, an average of 18 months]
Apgar score

Eligibility Criteria

Criteria

Ages Eligible for Study:

19 Years to 45 Years

Sexes Eligible for Study:

Female

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

gestational age between 36+0 to 41+6 weeks
singleton pregnancies in cephalic presentation
estimated fetal weight between 2.5 - 4.0 kg
cervical dilatation of 4 cm with intact membranes
normal fetal heart rate trace before artificial rupture of membranes

Exclusion Criteria:

Women with significant medical (eg. heart disease, pre-eclampsia, diabetes with high dose insulin, retroviral disease)
fetal abnormality (eg. fetal growth restriction or small for gestational age < 2.5 kg, suspected macrosomia > 4.0 kg, fetal anomaly)