Balloon + Oxytocin Versus Oral Misoprostol to Induce Labor in Case of PROM (RUBAPRO2)

Induction of Labor Clinical Trial

— RUBAPRO2  

Official title:

Balloon + Oxytocin Versus Oral Misoprostol to Induce Labor in Case of Premature Rupture of Membranes (PROM) at Term in Nulliparous: a Randomized Controlled Trial (RUBAPRO2).

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05568745
• Other study ID #: PHRC N 2020 GALLOT
• Secondary ID: 2022-A01479-3420
• Status: Recruiting
• Phase: Phase 4
• Start date: January 18, 2023
• Est. completion date: February 2026

Study information

• Verified date: January 2023
• Source: University Hospital, Clermont-Ferrand
• Contact: Lise LACLAUTRE
• Phone: +33473754963
• Email: promo_interne_drci[@]chu-clermontferrand.fr
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Premature rupture of membranes (PROM) at term complicates 6 to 22% of singleton pregnancies. Spontaneous labour occurs in 60-67% of these patients within 24h. If no effective uterine contraction occurs, induction of labour (IOL) is the strategy recommended by the French as well as the American College of Obstetricians and Gynecologists. The optimal strategy for IOL in case of PROM with an unfavourable cervix remains unknown and none of the studies conducted in nulliparous women showed the superiority of one induction method over another.

In the current project, we aimed to determine (1) if IOL with association of balloon catheter and oxytocin after 6 hours could increase the rate of delivery < 24h versus low dose of oral misoprostol (25 µg oral PGE1 every 2h) in case of PROM at term in nulliparous women and (2) patient satisfaction using EXIT survey assessed before hospital discharge.

Description:

Context : Premature rupture of membranes (PROM) at term complicates 6 to 22% of singleton pregnancies. Spontaneous labour occurs in 60-67% of these patients within 24hours. If no effective uterine contraction occurs, induction of labour (IOL) is the strategy recommended by the French as well as the American College of Obstetricians and Gynecologists. The optimal strategy for IOL in case of PROM with an unfavourable cervix remains unknown and none of the studies conducted in nulliparous women showed the superiority of one induction method over another1. Oral misoprostol (ProstaglandinE1, PGE1) usually demonstrated the lowest rate of c-section after IOL in general population and balloon catheter was associated with the lowest rate of uterine hyperstimulation. Recently, a comparison 1 to 1 between these two methods was conducted in singletons with comparable results. Despite recent studies demonstrating no higher risk of infectious complications using mechanical device in the context of PROM, only prostaglandins and oxytocin are usually recommended. Recently, Devillard et al. demonstrated that the combination of balloon catheter plus oxytocin systematically infused after 6 hours increased the rate of delivery <24h compared to dinoprostone vaginal insert group (90% versus 57.5% respectively) and decreased the time between induction and delivery in nulliparous group (17.0hours versus 26.5hours).

In the current project, we aimed to determine (1) if IOL with association of balloon catheter and oxytocin after 6 hours could increase the rate of delivery < 24hours versus low dose of oral misoprostol (25 µg oral PGE1 every 2h) in case of PROM at term in nulliparous women and (2) patient satisfaction using EXIT (EXperience of Induction Tool) survey assessed before hospital discharge.

We hypothesized that the rate of delivery < 24hours will be 15% higher in the group induced with balloon + oxytocin (estimated around 85 %) compared to the misoprostol group (estimated around 70 %). Patient satisfaction concerning experience of IOL will be assessed using a validated survey- the EXperience of Induction Tool (EXIT) - translated in French language (Beckman et al., 2017). We aimed to demonstrate a difference greater than an effect-size of 0.25.

Objectives: The main objective is to demonstrate higher rate of vaginal birth <24hours by insertion of a balloon catheter + oxytocin after 6hours, versus low dose of oral misoprostol (25 µg oral PGE1 every 2hours) in case of unfavorable cervix beyond 12 hours of PROM in nulliparous and to compare patient satisfaction using EXIT survey translated in French language before hospital discharge.

The secondary objectives are:

• To compare the rate of caesarean sections in the two groups.

• To compare the safety related to women of both induction methods in terms of maternal morbidities, uterine hyperstimulation, maternal infections and other reported adverse events (AEs).

• To compare the safety related to neonates of both induction methods in terms of neonatal morbidities, neonatal infections and other reported AEs.

Study type: Multi-center, randomized, controlled, open-label therapeutic trial with two parallel arms.

Number of centers: 5

Study Description:

The study group is the balloon catheter group with addition of oxytocin as early as 6h after the catheter insertion. After 12 hours of balloon insertion, induction of labour is continued by oxytocin alone. The control group corresponds to induction with misoprostol 25µg given orally (oral prostaglandin E1). The same dose is delivered every 2 hours until labour onset with a maximum of 8 administrations. Oxytocin can be started at least 4 hours after the last misoprostol administration.

Patients will be assigned by random allocation on a 1:1 basis in permuted blocks to either treatment group or control group using a dedicated, password-protected, SSL-encrypted website. To minimize the risk of imbalance between the study groups, the randomization will be stratified by trial site.

Primary endpoint: Hierarchical primary endpoint: (1) Proportion of patients vaginally delivered <24h and (2) patient satisfaction using EXIT survey assessed before hospital discharge.

Number of patients: 520

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 520
• Est. completion date: February 2026
• Est. primary completion date: February 2025
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Age > 18 years old,

• Pregnant, Gestational age = 37 weeks

• Singleton pregnancy with cephalic presentation

• Nulliparous

• PROM without labour beyond 12 hours

• Unfavourable cervix (Bischop score < 6)

• Able to give her informed consent

• Ability to comply with the requirement of the study

• Covered by the French Social Security welfare system

Exclusion Criteria:

• Unable to understand French language

• Contraindication for vaginal delivery

• Loss of meconium amniotic fluid (LA)

• Temperature > 38.2°C

• Intrauterine infection

• IUGR with Doppler anomaly

• Fetus with expected polymalformative syndrome

• Scarred womb

• Suspicion of genital herpes

• Known HIV seropositivity

• Placenta praevia

• Fetal death

• Abnormal FHR (Fetal Heart Rate)

• Contraindication to misoprostol:

• Allergy or hypersensibility

• Suspicion or confirmation of a scarred uterus following past surgical intervention

• Renal insufficiency

• Malformation of the uterus

• Contraindication to balloon:

• Vasa praevia, placenta praevia

• Invasive cervical cancer

• Contraindication to oxytocin

• Allergy or hypersensibility

• Dystocia

• Fragility or excessive distension of the uterus

• Uterine hypertonia or fetal distress when delivery is not imminent

• Cardiovascular disorders and severe preeclampsia

• Predisposition to amniotic embolism (in utero fetal demise, abruption).

• Patient subject to a legal protection order (curatorship or tutorship)

• Refusal to participate

Related Conditions & MeSH terms

• Cervical Ripening
• Fetal Membranes, Premature Rupture
• Induction of Labor
• Nulliparous
• Premature Birth
• Premature Rupture of Fetal Membranes
• Rupture

Intervention

Device:
• Balloon for cervical ripening (Teleflex French Dufour catheter CH20 reference 174000)
Balloon catheter is inserted by a resident or a physician under visual control. The expected volume injected in the balloon probe is 60 mL. No traction is performed on the catheter. The catheter is left in place for a maximum of 12 hours.

Drug:
• Oxytocin
Intravenous oxytocin addition (preceded or followed by epidural analgesia on patient's request) will be performed 6 hours after insertion of balloon catheter. Oxytocin is administered as an intravenous infusion (5 IU of oxytocin in 49 mL of 5% glucose*) at the lowest possible dose with the aim of achieving a maximum of three to four contractions per ten minutes. After appropriate uterine activity has been achieved, the rate of the oxytocin infusion is decreased or stopped.
• Misoprostol Oral Tablet
Patients will receive misoprostol 25 micrograms given orally (oral prostaglandin E1). The same dose will be given every 2 hours until beginning of labor with a maximum of 8 administrations.

Locations

Country	Name	City	State
France	CHU de Bordeaux	Bordeaux
France	CHU de Clermont-Ferrand	Clermont-Ferrand
France	Assistance Publique Hôpitaux de Paris- CHU Bicêtre	Le Kremlin-Bicêtre
France	CHU de Saint Etienne	Saint-Étienne
France	CHU de Toulouse	Toulouse

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital, Clermont-Ferrand

Country where clinical trial is conducted

France, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Vaginal delivery <24hours	Proportion of patients vaginally delivered <24hours (in %)	at birth
Primary	Patient satisfaction	Satisfaction of women concerning method of induction by the EXperience of Induction Tool (EXIT) validated in french language.	up to 4 days
Secondary	Duration from rupture to beginning of induction	in hours	at birth
Secondary	Duration between IOL and delivery	in hours	at birth
Secondary	Duration of balloon exposure or misoprostol exposure	in hours	at birth
Secondary	Misoprostol received	Total dose of misoprostol received (in µg)	at birth
Secondary	Bishop score on balloon removal	(comprised between 0 and 13)	at birth
Secondary	Balloon in place (yes/no)	Rate of balloon in place (%) at 12 hours after the beginning of induction	at birth
Secondary	Duration between induction and full cervical dilatation	Duration (in hours)	at birth
Secondary	Mode of delivery	Rate in %	at birth
Secondary	Post-partum hemorrhage	Rate in %	up to 4 days
Secondary	Rate of fever	Rate in %	during labor
Secondary	Rate of patients experiencing episode(s) of uterine hyperstimulation	Rate of patients experiencing episode(s) of uterine hyperstimulation (%) during labour (defined by the necessity to interrupt oxytocin and/or to inject pharmacological agents in the context of excessive number of contractions with or without abnormal FHR),	during labor
Secondary	Endometritis	Rate of endometritis in %	up to 4 days
Secondary	Duration of hospital stay	Duration (in days)	up to 4 days
Secondary	Birth weight of the newborn	in grammes	at birth
Secondary	Apgar score < 7	Neonatal endpoint (yes/no)	5min after birth
Secondary	pH umbilical artery	pH at the umbilical artery	at birth
Secondary	Base defect and lactate (umbilical artery)	mmol/L	at birth
Secondary	Neonatal tranfer	Rate of neonatal transfer to intensive care unit or neonatology unit	up to 4 days
Secondary	maternal-fetal infection	Rate of maternal-fetal infection in %	up to 4 days