The Trial of Pessary After Laser for TTTS

Study Overview
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Brief Summary
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Placing a cervical pessary in severe twin-to-twin transfusion syndrome (TTTS) cases treated by fetoscopic laser coagulation (FLC) decreases the spontaneous preterm birth rate.

Detailed Description
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Monochorionic (MC) twin pregnancies present with a high rate of fetal complications, most of them associated with the placental vascular anastomoses. Fetoscopic laser coagulation (FLC) is a surgical technique that allows minimally invasive access into the uterus and has emerged as a useful tool in the management of the most common and severe of these complications, twin to twin transfusion syndrome (TTTS). Even though, preterm birth remains a common cause of adverse outcome because TTTS is associated with a 29% risk of delivering before 28 weeks. A short cervical length (CL), defined as a CL ≤ 25 mm, detected by transvaginal ultrasound is an independent risk factor for preterm birth in twin pregnancies but no effective treatment has been described to prevent it. Although is usually accepted that in twin pregnancies cerclage may increase the risk of preterm birth, Salomon and co-workers, found that in cases of TTTS with a CL below the 5th percentile (15 mm) at the time of surgery, performing an emergency cerclage prolonged the pregnancy and allow for better outcome, But still preterm birth after FLC remains a big challenge, so new methods to prevent it must be investigated. Previous studies in singletons and twins have shown that the use of cervical pessary significantly reduces the frequency of birth before 32 weeks and prolongs pregnancy. The advantage of using cervical pessary is that it is less invasive than cerclage and can be removed easily. That's the reason why pessaries could be considered an alternative, non invasive option to prevent preterm birth in cases of twin to twin transfusion syndrome (TTTS) treated by laser surgery.

Official Title
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Arabin Cervical Pessary for Prevention of Preterm Birth in Cases of Twin-to-twin Transfusion Syndrome Treated by Fetoscopic Laser Coagulation: The PECEP Laser Trial

Conditions
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Premature Birth

Intervention / Treatment
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* Device: Arabin Cervical Pessary


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Monochorionic twin pregnancies with severe TTTS requiring intrauterine surgery Less than 26 weeks Minimal age of 18 years Informed consent signature Exclusion Criteria: Major fetal abnormalities (requiring surgery or leading to infant death or severe handicap) Cerclage prior to randomisation Uterine malformation Placenta previa Active vaginal bleeding at the moment of randomization Spontaneous rupture of membranes at the time of randomization Death of both twins after the surgery Monochorionic-monoamniotic twin pregnancy Silicone allergy Current participation in other RCT

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Usual management<br>Usual management of monochorionic pregnancy without the pessary placement | |
| Other: Arabin Cervical Pessary<br>The pessary will be inserted 24 hours after fetal surgery in the exploration room. This procedure does not need anaesthesia and it does not need to be done in a surgery room. During the following explorations the correct placement of the pessary is assessed, and if it does not, it can be easily adjusted. The pessary will be removed at 37 weeks of gestation, or before if any unexpected event occurs. | Device: Arabin Cervical Pessary<br>* The Arabin cervical pessary, which is CE-certified for preventing SPB (CE 0482 / EN ISO 13485: 2003 annex III of the council directive 93/42 EEC). It is a vaginal device which is used to treat pregnant women for preventing spontaneous preterm birth. This device can be easily placed around the uterine cervix without pain.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Delivery before 32 weeks | Rate of delivery before 32 weeks | Within the first 15 days after delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Birth weight | Median weight (g) of the newborns at birth. | Within the first 15 days after delivery | 
| Fetal or neonatal death | Rate of intrauterine demise or neonatal death during the first 24 hours. | Within the first 15 days after the death | 
| Neonatal morbidity | Rate of major adverse neonatal outcomes before discharge from the hospital. | 30 days after the discharge from the hospital | 
| Significant maternal adverse events | Rate of heavy bleeding (bleeding that requires a medical intervention), cervical tear (cervical rupture due to the pessary placement), and/or uterine rupture (rupture of the uterus due to contractions or surgery). | Within 15 days after discharge from the hospital | 
| Physical or psychological intolerance to pessary | Discomfort or pain due to the pessary that makes daily life uncomfortable (number of cases). | Within 15 days after discharge from hospital | 
| Preterm birth before 37 weeks | Rate of delivery before 36+6 weeks | Within 15 days after delivery | 
| Rupture of membranes before 32 weeks | Rupture of amniotic membranes before 31+6 weeks | Within 15 days after delivery | 
| Hospitalisation for threatened preterm labour before 32 weeks | Requirement of hospitalisation due to preterm contractions that need medical treatment to try to stop them before 31+6 weeks (rate). | Within 15 days after delivery | 
| Time to birth |  | Within 15 days after delivery | 
| Preterm birth before 34 weeks | rate of delivery before 33+6 weeks | Within 15 days after delivery | 
| Preterm birth before 30 weeks | rate of delivery before 29+6 weeks | Within 15 days after delivery | 
| Preterm birth before 28 weeks | rate of delivery before 27+6 weeks | Within 15 days after delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Monochorionic pregnancy, Twin to twin transfusion syndrome, Cervical pessary, Cervical length