Correlation Between the Polymorphism ofβ2 AR and the Labor Progress After Labor Analgesia

Study Overview
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Brief Summary
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Labor and delivery is a unique physiological experience of women. Inappropriate length of labor progress during vaginal delivery may produce great risks for mother and fetus. Especially the slow progress is one of the most important reasons for the occurrence of cesarean section during vaginal delivery, which still with a high incidence in recent years.Previous studies have found that there was a significant correlation between the genetic polymorphisms of β 2-adrenergic receptor (β2AR) and the duration of vaginal delivery.Therefore, the researchers intend to investigate the distribution of β2-adrenergic receptor (β2AR) genetic polymorphisms among Chinese parturient and observe the relationship between the genetic polymorphisms and labor process after labor analgesia.

Official Title
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Principal Investigator

Conditions
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Labor Analgesia

Intervention / Treatment
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* Genetic: β2AR polymorphism


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Nulliparous women Required labor analgesia Chinese Spontaneous labor Exclusion Criteria: Contraindications for epidural analgesia Allergic to opioids and/or local anesthetics Failed to performing epidural catheterization Organic dysfunction Those who were not willing to or could not finish the whole study at any time Using or used in the past 14 days of the monoamine oxidase inhibitors Alcohol addictive or narcotic dependent patients Subjects with a nonvertex presentation or scheduled induction of labor Twin gestation and breech presentation

Ages Eligible for Study
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Minimum Age: 23 Years
Maximum Age: 43 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| β2AR Arg16Arg (AA group)<br>People with β2AR Arg16Arg genotype. | Genetic: β2AR polymorphism<br> <br> |
| β2AR Arg16Gly (AG group)<br>People with β2AR Arg16Gly genotype. | Genetic: β2AR polymorphism<br> <br> |
| β2AR Gly16Gly (GG group)<br>People with β2AR Gly16Gly genotype. | Genetic: β2AR polymorphism<br> <br> |
| β2AR Gln27Gln (CC group)<br>People with β2AR Gln16Gln genotype. | Genetic: β2AR polymorphism<br> <br> |
| β2AR Gln27Glu (CG group)<br>People with β2AR Gln27Glu genotype. | Genetic: β2AR polymorphism<br> <br> |
| β2AR Glu27Glu (GG group)<br>People with β2AR Glu27Glu genotype. | Genetic: β2AR polymorphism<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| total labor process | time from the regular uterus contractions until completed childbirth, assessed up to about 24h | up to about 24h | 
| duration of the first stage | time from the regular uterus contractions to full cervix dilation,assessed up to about 20h | up to about 20h | 
| duration of the second stage | time from full cervix dilation to the complete childbirth, assessed up to about 2h | up to about 2h | 
| Maternal visual analogue scale | At time of initiation of analgesia and hourly thereafter until 2 hours postpartum (approximately 10 hours) | At time of initiation of analgesia and hourly thereafter until 2 hours postpartum (approximately 10 hours) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| method of delivery | At time of placental delivery | At time of placental delivery | 
| Maternal modified Bromage scale | At time of initiation of analgesia and hourly thereafter until 2 hours postpartum (approximately 10 hours) | At time of initiation of analgesia and hourly thereafter until 2 hours postpartum (approximately 10 hours) | 
| Rescue boluses, n of rescue boluses, and the consumption of the ropivacaine/sufentanil mixture | At two hours postpartum | At two hours postpartum | 
| Maternal satisfaction with analgesia | At two hours postpartum | At two hours postpartum | 
| Use of oxytocin after analgesia | At twenty-four hours postpartum | At twenty-four hours postpartum | 
| Neonatal Apgar scale | At the first and fifth minutes after baby was born | At the first and fifth minutes after baby was born | 
| Maximal oxytocin dose | At twenty-four hours postpartum | At twenty-four hours postpartum | 
| Maternal heart rate, respiratory rate, and blood pressure | At time of initiation of analgesia and hourly thereafter until 4 hours postpartum (approximately 12 hours) | At time of initiation of analgesia and hourly thereafter until 4 hours postpartum (approximately 12 hours) | 
| Neonatal weight | At delivery | At delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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β2-adrenergic receptor, genetic polymorphisms, labor progress