Combined Misoprostol and Cervical Balloon vs Misoprostol Alone for Induction on the First Day in Primiparas
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Misoprostol, Misoprostol plus Cervical Balloon.
- Who it may be relevant to
- Registry conditions: Primiparous Women. Basic parameters: 20 years — 45 years · Female.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Efficacy of Intravaginal Misoprostol Combined With Cervical Balloon Versus Misoprostol Alone for Induction of Labor on the First Day in Primiparous Women: A Randomized Controlled Trial
Overview
Misoprostol (a prostaglandin E1 analog) is commonly used for cervical ripening and labor induction via vaginal administration. The cervical balloon is another commonly used method that provides mechanical cervical dilation. Both methods are low-cost and widely available. Some meta-analyses have suggested that combined use may shorten the duration of labor, reduce the frequency of tachysystole, and lower NICU admission rates without increasing the risk of cesarean section. However, existing studies are heterogeneous and lack data from Asian populations. This study is being done to see whether combining two common methods of labor induction-misoprostol (a medicine placed in the vagina) and a cervical balloon (placed in the cervix) on the first day of induction-can shorten the time from the start of induction to delivery in first-time mothers during pregnancy . Participants will be randomly assigned to one of two groups: one group will receive misoprostol alone (standard care) on the first day of induction, and the other group will receive misoprostol plus a cervical balloon on the first day of induction. The main outcome measured is the time from the start of induction to delivery. The study will also look at safety outcomes, including the rate of cesarean section, maternal complications, and newborn outcomes.
Detailed description
This is a single-center, randomized, open-label, superiority randomized controlled trial. Participants will be randomly assigned in a 1:1 ratio to either the intervention group (misoprostol plus cervical balloon on the first day of induction) or the control group (misoprostol alone on the first day of induction).
IPRIMARY OUTCOME:
Time from initiation of labor induction to delivery (hours).
SECONDARY OUTCOMES:
Time from induction to amniotomy (min), time from induction to spontaneous membrane rupture (h), time from induction to onset of labor (min), duration of balloon use (min), duration of oxytocin use (min), duration of latent phase (h), duration of first and second stages of labor (min), mode of delivery, degree of perineal laceration, indications for forceps/episiotomy/cesarean section, fetal distress, intrauterine infection, neonatal outcomes (birth weight, Apgar score, umbilical artery pH/BE, NICU admission), and maternal hemoglobin difference before and after delivery. Safety outcomes include placental abruption, septic shock, and severe postpartum hemorrhage.
SAMPLE SIZE:
Based on historical data from 90 primiparous women at Peking University First Hospital (June 2025), the mean induction-to-delivery interval was 39.07 ± 19.92 hours. Assuming an 8-hour reduction in the intervention group, with a two-sided alpha of 0.05, power of 80%, and a 10% dropout rate, each group requires 110 participants (total 220).
STATISTICAL ANALYSIS:
Continuous variables will be compared using t-test or Mann-Whitney U test as appropriate. Categorical variables will be compared using chi-square or Fisher's exact test. Multivariable linear regression and logistic regression will be used for adjusted analyses. Subgroup analyses will be performed by type of hyperglycemia, age, BMI, and baseline Bishop score.
ETHICS AND REGISTRATION:
This study has been approved by the Biomedical Research Ethics Committee of Peking University First Hospital (Approval No. 2025R0393-0002, dated September 25, 2025). The study is registered on ClinicalTrials.gov.
STUDY PERIOD:
June 2026 to December 2026.
Interventions
- Drug Misoprostol
25 μg misoprostol tablet placed in the posterior vaginal fornix for cervical ripening and labor induction on the first day. May be repeated up to 3-4 times based on uterine contraction response (monitored every 2-4 hours). - Device Misoprostol plus Cervical Balloon
A Cervical balloon with 80 mL sterile water inflation placed intracervically for mechanical cervical dilation. The balloon is left in place for up to 12-24 hours or until spontaneous expulsion.
Primary outcome measures
- Time from initiation of labor induction to delivery [Time frame: Time from initiation of induction measures on the first day of induction to delivery (control group: time of first misoprostol placement; intervention group: time of cervical balloon and misoprostol placement).]
Secondary outcome measures (12)
- Time from Induction to Amniotomy [Time frame: From start of induction to amniotomy]
- Time from Induction to Spontaneous Membrane Rupture [Time frame: From start of induction to spontaneous rupture]
- Time from Induction to Onset of Labor [Time frame: From start of induction to onset of labor]
- Duration of Balloon Use [Time frame: From balloon insertion to removal, assessed during the induction period (up to 24 hours).]
- Duration of Oxytocin Use [Time frame: From start to stop of oxytocin infusion, assessed during labor]
- Duration of Latent Phase of Labor [Time frame: From onset of labor to active phase, assessed during labor]
- Duration of First and Second Stages of Labor [Time frame: From full dilation to delivery, assessed during the second stage]
- Mode of Delivery [Time frame: At the time of delivery.]
- Degree of Perineal Laceration [Time frame: Immediately after vaginal delivery.]
- Indications for Forceps/Episiotomy/Cesarean Section [Time frame: At the time of the operative intervention (during labor/delivery).]
- Fetal Distress [Time frame: During labor, assessed up to delivery.]
- Intrauterine Infection [Time frame: During labor and up to 48 hours postpartum.]
Eligibility criteria
Inclusion criteria
- Age 20-45 years at delivery
- Singleton pregnancy
- Primiparous
- Cephalic presentation
- Cervical Bishop score ≤ 5
- No history of stillbirth
Exclusion criteria
- Multiple pregnancy
- Contraindications to vaginal delivery
- Mental disorders (depression or anxiety)
- Preterm labor (< 37 weeks)
- Intrauterine fetal death
- Previous uterine surgery
- Premature rupture of membranes
- Abnormal fetal heart rate tracing
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
Center list to be confirmed — check the primary protocol.
Identifiers
NCT: NCT07690007 · 2025R0393-0002