Cerclage for Twins With Short Cervical Length ≤ 15mm

Study Overview
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Brief Summary
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This is a multicenter randomized study designed to determine if ultrasound indicated cerclage reduces the incidence of spontaneous preterm birth <34 weeks in asymptomatic women with twin gestations and cervical length ≤15mm, diagnosed by transvaginal ultrasound between 16 to 23 6/7 weeks of gestation.

Detailed Description
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Twin pregnancies have 59% incidence of preterm delivery (before 37 weeks of gestation), with increased perinatal mortality and neonatal morbidity. No therapy has proven effective in preventing preterm birth in twins. The transvaginal cervical length (TVCL) performed before 24 weeks have been determined to be the best tool to identified women with twin pregnancy at risk of preterm birth (PTB). When short TVCL is identified before 24 weeks, the risk of preterm birth is 60%-70% for TVCL ≤25mm and 80%-90% for TVCL ≤15mm. There are a small number of case reports of cervical cerclage in twin pregnancies with cervical length ≤15mm that suggest decreased preterm birth by 80%. The investigators' objective is to determine if ultrasound indicated cerclage in reduces the incidence of spontaneous preterm birth <34 weeks and improve perinatal outcome in asymptomatic women with twin gestations and cervical length ≤15mm between 16 to 23 6/7 weeks of gestation.

Official Title
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Cervical Cerclage for Preventing Spontaneous Preterm Birth in Twin Pregnancies With Transvaginal Ultrasound Cervical Length ≤ 15mm: a Study Protocol for a Randomized Clinical Trial

Conditions
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Twin Pregnancy With Antenatal Problem, Preterm Birth, Short Cervix

Intervention / Treatment
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* Procedure: Cervical cerclage


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pregnant women more than 18 years of age (limits the participants to female gender) Diamniotic twin pregnancy Asymptomatic Transvaginal cervical length ≤ 15 mm between 16-23 6/7 weeks gestation Exclusion Criteria: Singleton or higher order than twins multiple gestation Transvaginal cervical length >15mm Cervical dilation with visible amniotic membranes Amniotic membranes prolapsed into the vagina Fetal reduction after 14 weeks form higher order Monoamniotic twins Twin-twin transfusion syndrome Ruptured membranes Major fetal structural anomaly Fetal chromosomal abnormality Cerclage already in place for other indication Active vaginal bleeding Clinical chorioamnionitis Placenta previa Painful regular uterine contractions Labor

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cervical cerclage + vaginal progesterone<br>Cervical cerclage in twin pregnancy with transvaginal cervical length ≤15mm and Daily vaginal progesterone 400mg from diagnosis of short cervix to 36 weeks | Procedure: Cervical cerclage<br>* Cervical cerclage indicated by short cervix ≤15mm<br>|
| No Intervention: Vaginal progesterone<br>Daily vaginal progesterone 400mg from diagnosis of short cervix to 36 weeks | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Preterm delivery less than 34 weeks | Incidence of preterm birth less than 34 weeks (any indication) | at delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Spontaneous preterm birth rates | Incidence of spontaneous preterm birth less than 34 weeks | at delivery | 
| Preterm delivery less than <32 weeks, <28 weeks, or <24 weeks | Incidence of preterm birth less than <32 weeks, <28 weeks, or <24 weeks | at delivery | 
| Mean gestational age at delivery | Mean value of gestational age at delivery (weeks) | at delivery | 
| Birth weight at birth | Mean value (grams) | at delivery | 
| Gestational age at spontaneous rupture of membranes | Mean value (weeks) through study completion | at delivery | 
| Premature rupture of membranes | Incidence | at delivery | 
| Chorioamnionitis | Incidence | at delivery | 
| Composite adverse neonatal outcome | Includes necrotizing enterocolitis, intraventricular hemorrhage (grade 3 or higher), respiratory distress syndrome, bronchopulmonary dysplasia, retinopathy, blood-culture proven sepsis | Incidence between birth and 28 days of age | 
| Neonatal death | Incidence | Between birth and 28 days of age | 
| Maternal death | Incidence | Between birth and 6 weeks postpartum | 
| Interval between diagnosis and delivery | Mean value (days) through study completion | at delivery |