Balloon Catheter Combined With Oxytocin Induction Among the Pregnant Women With Previous Cesarean Section

Study Overview
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Brief Summary
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This study is a multi-center, prospective, observational clinical trial study. 924 full-term pregnant women will be enrolled as subjects, and the ratio of eligible subjects in the two groups is 1:1. In the prior cesarean section group, pregnant women with one previous cesarean section who are willing to try to the trial of labor after cesarean (TOLAC) and in accordance with the criteria according to the 2016 China vaginal birth after cesarean (VBAC) clinical management guidelines will be enrolled and recorded by our homemade registration form of TOLAC. In the control group, pregnant women after 39 weeks of gestation without vaginal labor contraindications will be enrolled. Whether in the experimental group or the control group, their cervical bishop score was less than 6 points, and they all will be induced by balloon catheter + oxytocin. After 96h, their final delivery mode will be recorded. In the following 42 days postpartum, their complications and the neonatal outcome will be followed up.

Official Title
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To Study the Effectiveness and Safety of Balloon Catheter Combined With Oxytocin Induction Among the Pregnant Women With Previous Cesarean Section: Multicenter, Prospective, Observational Study

Conditions
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Trial of Labor After Cesarean, Vaginal Birth After Cesarean, Bishop Score, Failed Mechanical Induction, Balloon Catheter for Labor Induction, Unfavorable Cervix

Intervention / Treatment
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* Device: Balloon catheter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Volunteers sign the informed consent; Age: 20-40 years; Singleton, a cephalic presentation; No contradiction to vaginal delivery; 5.39 42 weeks. Exclusion criteria: Konwn contraindication to vaginal delivery or severe complications; Multiple gestation; Uterine malformation; Severe psychiatric disorder; Without family's support.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cesarean section group<br>In the cesarean section group, all the pregnant women had only one prior cesarean section. | Device: Balloon catheter<br>* In the two groups, if their bishop score <6, they will receive the cervical riening by the balloon catheter, and then the oxytocin if necessary.<br>|
| Non-cesarean section group<br>In the non-cesarean section group, all the pregnant women are primipara，and never had a cesarean section. | Device: Balloon catheter<br>* In the two groups, if their bishop score <6, they will receive the cervical riening by the balloon catheter, and then the oxytocin if necessary.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| vignial birth rate | After the treatment of balloon catheter for 12 hours +oxytocin induction for up tp 72 hours, the mode of delivery will be konwn and recorded. | up to 84 hours |