%0 Journal Article %T Study protocol for two randomised controlled trials evaluating the effects of Cerclage in the reduction of extreme preterm birth and perinatal mortality in twin pregnancies with a short cervix or dilatation: the TWIN Cerclage studies. %A van Gils L %A de Boer MA %A Bosmans J %A Duijnhoven R %A Schoenmakers S %A Derks JB %A Prins JR %A Al-Nasiry S %A Lutke Holzik M %A Lopriore E %A van Drongelen J %A Knol MH %A van Laar JOEH %A Jacquemyn Y %A van Holsbeke C %A Dehaene I %A Lewi L %A van der Merwe H %A Gyselaers W %A Obermann-Borst SA %A Holthuis M %A Mol BW %A Pajkrt E %A Oudijk MA %J BMJ Open %V 14 %N 5 %D 2024 May 10 %M 38729756 %F 3.006 %R 10.1136/bmjopen-2023-081561 %X BACKGROUND: Twin pregnancies have a high risk of extreme preterm birth (PTB) at less than 28 weeks of gestation, which is associated with increased risk of neonatal morbidity and mortality. Currently there is a lack of effective treatments for women with a twin pregnancy and a short cervix or cervical dilatation. A possible effective surgical method to reduce extreme PTB in twin pregnancies with an asymptomatic short cervix or dilatation at midpregnancy is the placement of a vaginal cerclage.
METHODS: We designed two multicentre randomised trials involving eight hospitals in the Netherlands (sites in other countries may be added at a later date). Women older than 16 years with a twin pregnancy at <24 weeks of gestation and an asymptomatic short cervix of ≤25 mm or cervical dilatation will be randomly allocated (1:1) to both trials on vaginal cerclage and standard treatment according to the current Dutch Society of Obstetrics and Gynaecology guideline (no cerclage). Permuted blocks sized 2 and 4 will be used to minimise the risk of disbalance. The primary outcome measure is PTB of <28 weeks. Analyses will be by intention to treat. The first trial is to demonstrate a risk reduction from 25% to 10% in the short cervix group, for which 194 patients need to be recruited. The second trial is to demonstrate a risk reduction from 80% to 35% in the dilatation group and will recruit 44 women. A cost-effectiveness analysis will be performed from a societal perspective.
BACKGROUND: This study has been approved by the Research Ethics Committees in the Netherlands on 3/30/2023. Participants will be required to sign an informed consent form. The results will be presented at conferences and published in a peer-reviewed journal. Participants will be informed about the results.
BACKGROUND: ClinicalTrials.gov, NCT05968794.