Premature Birth
Conditions
Keywords
Monochorionic pregnancy, Twin to twin transfusion syndrome, Cervical pessary, Cervical length
Brief summary
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
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.
Interventions
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.
Sponsors
Study design
Eligibility
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Delivery before 32 weeks | Within the first 15 days after delivery | Rate of delivery before 32 weeks |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Fetal or neonatal death | Within the first 15 days after the death | Rate of intrauterine demise or neonatal death during the first 24 hours. |
| Neonatal morbidity | 30 days after the discharge from the hospital | Rate of major adverse neonatal outcomes before discharge from the hospital. |
| Significant maternal adverse events | Within 15 days after discharge from the hospital | 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). |
| Physical or psychological intolerance to pessary | Within 15 days after discharge from hospital | Discomfort or pain due to the pessary that makes daily life uncomfortable (number of cases). |
| Preterm birth before 37 weeks | Within 15 days after delivery | Rate of delivery before 36+6 weeks |
| Birth weight | Within the first 15 days after delivery | Median weight (g) of the newborns at birth. |
| Hospitalisation for threatened preterm labour before 32 weeks | Within 15 days after delivery | Requirement of hospitalisation due to preterm contractions that need medical treatment to try to stop them before 31+6 weeks (rate). |
| Time to birth | Within 15 days after delivery | — |
| Preterm birth before 34 weeks | Within 15 days after delivery | rate of delivery before 33+6 weeks |
| Preterm birth before 30 weeks | Within 15 days after delivery | rate of delivery before 29+6 weeks |
| Preterm birth before 28 weeks | Within 15 days after delivery | rate of delivery before 27+6 weeks |
| Rupture of membranes before 32 weeks | Within 15 days after delivery | Rupture of amniotic membranes before 31+6 weeks |
Countries
Belgium, Germany, Spain