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Heated Saline in Cervical Balloon for Labor Induction, a RCT

Effect of Heated Saline in Duration of Cervical Ripening in Women Having Labor Induction With Cervical Balloon: a Randomized Controlled Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05864326
Enrollment
290
Registered
2023-05-18
Start date
2023-10-16
Completion date
2025-05-30
Last updated
2025-06-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cervical Ripening, Induction of Labor, Mechanical Method, Unfavorable Cervix

Keywords

Cervical ripening, Induction of Labor, Unfavorable cervix, Mechanical method

Brief summary

This study is a single-center, randomized, two-arm, controlled trial, including women requiring cervical ripening during the process Induction of Labor using Balloon catheter (BC). The primary objective of the study is to determine if the use of heated saline in the BC used for cervical ripening reduces the length of BC duration. Participants will be allocated to : * Intervention or warm group: the BC will be filled with heated saline water up to 40° C * Standard or room temperature group: the BC will be filled with saline water at room temperature.

Detailed description

Background and Rationale: Induction of Labor (IOL) is one of the most common interventions in obstetrics. IOL is performed due to fetal, maternal or pregnancy complications to reduce the risk of complication. IOL methods will depend of the state of the cervix at the beginning of the procedure. If cervix is considered unfavorable (Bishop score ≤ 5) an initial phase of ripening is usually proposed. There are various methods of cervical ripening, which can be divided into non-pharmacological (e.g., mechanical methods with transcervical Foley catheter or Cook balloon) and pharmacological (e.g., prostaglandins). IOL can be a long-lasting procedure, especially when cervical ripening is necessary. Two recent, small studies have shown that the use of warm fluid to inflate the balloon catheter (BC) inserted through the cervix reduces the time of cervical ripening, hence potentially reducing the time of IOL. These results are the only data available regarding the use of saline at different temperatures for inflating the balloon in mechanical methods and show promising effects in terms of reduction in the length of the cervical ripening and labor. The cervix is mainly composed of collagen. Studies show that the use of heat on connective tissue increase the potential elongation of collagen tissue and the denaturation of this protein. We hypothesize that the use of heat in the cervical ripening can accelerate the denaturation of the collagen and accelerate the softening of the cervix and therefore reduce the duration of cervical ripening and labor. Objective(s): The primary objective of the study is to determine if the use of heated saline in the BC used for cervical ripening reduces the length of BC duration, defined as the time from the insertion to the expulsion or artificial removal of the BC. The secondary objectives are to evaluate if the use of heated saline compared with room temperature: 1. Decreases the length from the start of the induction until the achievement of a favorable cervix (Bishop score \>5). 2. Decreases the length from the start of the induction until full dilation 3. Decreases the length from the start of the induction until delivery 4. Increases the rate and the speed of spontaneous rupture of membranes (ROM) during cervical ripening 5. Impacts on the rate of cesarean delivery. 6. Impacts on the pain and the satisfaction in women undergoing cervical ripening 7. Impacts on obstetrical and neonatal complications Study Design: Prospective, single-center, randomized, two-arm, controlled trial, including women requiring cervical ripening during the process IOL using Balloon catheter Number of Participants with Rationale: A total of 290 women will be recruited (145 women in each group) in order to show a reduction in the duration of BC placement, considering a significance criterion set to 0.05 (alpha, two- tailed), and an expected power of at least 90%. Study procedures: Patients will be allocated in one of this two groups: * Intervention or warm group: the BC will be filled with heated saline water up to 40° C * Standard or room temperature group: the BC will be filled with saline water at room temperature. In both groups, the insertion of the BC will be done following the same procedure: The operator will introduce a 14Fr or 18Fr Balloon catheter through the cervical canal, up above the internal orifice using a long Pean clamp and inflate the internal balloon with 30 to 80ml of saline water (NaCl 0.9%) -either heated or unheated, depending on the allocation group- according to the mechanic resistance with a graduated syringe. Statistical Considerations Main analysis will be performed on an intention-to-treat basis. The main outcome will be evaluated by plotting survival functions according to the allocation group, using the Kaplan-Meier estimator. The associations will be considered as statistically significant when the p-value is below 0.05 (probability of type I error = 0.05). This analysis is also planned for objectives 2 (interval from beginning of IOL and achievement of a favorable cervix) and 3 (interval from beginning of IOL and delivery). For the other outcomes, comparison will be performed using Fisher's exact test, Student's t-test or the Mann-Whitney U test, according to the type of variable.

Interventions

DEVICEWarm group

The operator will introduce a 14Fr or 18Fr Balloon catheter through the cervical canal, up above the internal orifice using a long Pean clamp and inflate the internal balloon with 30 to 80ml of Heated saline water (NaCl 0.9%) at 40°C - according to the mechanic resistance with a graduated syringe.

DEVICERoom temperature group

The operator will introduce a 14Fr or 18Fr Balloon catheter through the cervical canal, up above the internal orifice using a long Pean clamp and inflate the internal balloon with 30 to 80ml of unheated saline water (NaCl 0.9%) - according to the mechanic resistance with a graduated syringe.

Sponsors

Begona Martinez de Tejada
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Prospective, single-center, randomized, two-arm, controlled trial, including women requiring cervical ripening during the process IOL using Balloon catheter

Eligibility

Sex/Gender
FEMALE
Age
16 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* Gestational age at or over 35 weeks * Singleton pregnancy * Alive fetus * Cephalic presentation * Maternal age ≥ 16 years

Exclusion criteria

* Active labor (dilated cervix with spontaneous uterine contractions) * Prelabor rupture of membranes * \>1 Previous cesarean delivery * Fetal malformation leading to a possible obstruction of labor (e.g., hydrocephaly, exteriorized fetal tumors, etc.) * Maternal or fetal disease with indication to accelerate labor (start oxytocin stimulation within 6 hours after insertion of the BC (e.g., pre-eclampsia, chorioamnionitis, etc.)\] * Counterindication to vaginal delivery * Impossibility to give consent to participation

Design outcomes

Primary

MeasureTime frameDescription
To determine if the use of heated saline in the Balloon Catheter (BC), used for cervical ripening, reduces the length of BC duration, defined as the time from the insertion to spontaneous expulsion or artificial removal of the BC.Through study completion, an average of 1.5 yearsDuration of BC (i.e., positioning of the transcervical catheter): interval between insertion and retrieval, either after spontaneous expulsion or artificial retrieval.

Secondary

MeasureTime frameDescription
Decreases the length from the start of the induction until full dilationThrough study completion, an average of 1.5 yearsLength from the start of the BC insertion until fully dilation
Decreases the length from the start of the induction until the deliveryThrough study completion, an average of 1.5 yearsLength from the start of the BC insertion until the delivery
Increases the rate and the speed of spontaneous rupture of membranes (ROM) during cervical ripeningThrough study completion, an average of 1.5 yearsSpontaneous rupture of membranes (ROM) during cervical ripening or labor (Yes/No) \- If Yes, length from the insertion of the BC until spontaneous ROM.
To evaluate if the use of heated saline compared with room temperature Decreases the length from the start of the induction until the achievement of a favorable cervix (Bishop score >5)Through study completion, an average of 1.5 yearsLength of cervical ripening phase, defined as the interval between catheter insertion and the achievement of a favorable cervix, defined as Bishop score \>5.
Impacts on the pain and the satisfaction in women undergoing cervical ripeningThrough study completion, an average of 1.5 yearsPain after catheter insertion assessed using a numeric rating scale (NRS, where NRS = 0 equals no pain and NRS = 10 represents the worst possible pain suffered by the participant). Participants satisfaction of the whole using a five-point Likert scale (1, very dissatisfied; 2, dissatisfied; 3, Enough Satisfied; 4, Satisfied; and 5, very satisfied)
Impacts on obstetrical and neonatal complicationsThrough study completion, an average of 1.5 yearsPresence of obstetrical complications or neonatal complications
Impacts on the rate of cesarean deliveryThrough study completion, an average of 1.5 yearsMode of delivery (vaginal delivery vs. cesarean delivery)

Countries

Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026