title: Pessaries in multiple pregnancy as a prevention of preterm birth: the ProTwin Trial.
abstract: BACKGROUND
  Multiple pregnancies are at high risk for preterm birth, and therefore an important cause of infant mortality and morbidity. A pessary is a simple and potentially effective measure for the prevention of preterm birth. Small studies have indicated its effectiveness, but large studies with sufficient power on the subject are lacking. Despite this lack of evidence, the treatment is at present applied by some gynaecologists in The Netherlands.
  
  
  METHODS
  We aim to investigate the hypothesis that prophylactic use of a cervical pessary will be effective in the prevention of preterm delivery and the neonatal mortality and morbidity resulting from preterm delivery in multiple pregnancy. We will evaluate the costs and effects of this intervention. At study entry, cervical length will be measured. Eligible women will be randomly allocated to receive either a cervical pessary or no intervention. The cervical pessary will be placed in situ at 16 to 20 weeks, and will stay in situ up to 36 weeks gestation or until delivery, whatever comes first.The primary outcome is composite bad neonatal condition (perinatal death or severe morbidity). Secondary outcome measures are time to delivery, preterm birth rate before 32 and 37 weeks, days of admission in neonatal intensive care unit, maternal morbidity, maternal admission days for preterm labour and costs. We need to include 660 women to indicate a reduction in bad neonatal outcome from 7.2% without to 3.9% with a cervical pessary, using a two-sided test with an alpha of 0.05 and a power of 0.80.
  
  
  CONCLUSIONS
  This trial will provide evidence on whether a cervical pessary will decrease the incidence of early preterm birth and its concomitant bad neonatal outcome in multiple pregnancies.
  
  
  BACKGROUND
  Current Controlled Trials: NTR 1858.
authors.affiliation: Department of Obstetrics and Gynaecology, Onze Lieve Vrouwe Gasthuis Amsterdam, The Netherlands. protwintrial@gmail.com
authors.forename: Maud A
authors.initials: MA
authors.lastname: Hegeman
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Bekedam
authors.forename: Kitty Wm
authors.initials: KW
authors.lastname: Bloemenkamp
authors.forename: Anneke
authors.initials: A
authors.lastname: Kwee
authors.forename: Dimitri Nm
authors.initials: DN
authors.lastname: Papatsonis
authors.forename: Joris Am
authors.initials: JA
authors.lastname: van der Post
authors.forename: Arianne C
authors.initials: AC
authors.lastname: Lim
authors.forename: Hubertina Cj
authors.initials: HC
authors.lastname: Scheepers
authors.forename: Christine
authors.initials: C
authors.lastname: Willekes
authors.forename: Johannes J
authors.initials: JJ
authors.lastname: Duvekot
authors.forename: Marc
authors.initials: M
authors.lastname: Spaanderman
authors.forename: Martina
authors.initials: M
authors.lastname: Porath
authors.forename: Jim
authors.initials: J
authors.lastname: van Eyck
authors.forename: Monique C
authors.initials: MC
authors.lastname: Haak
authors.forename: Marielle G
authors.initials: MG
authors.lastname: van Pampus
authors.forename: Hein W
authors.initials: HW
authors.lastname: Bruinse
authors.forename: Ben Willem J
authors.initials: BW
authors.lastname: Mol
mesh_terms: D054791:Cervical Length Measurement; D002985:Clinical Protocols; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D009426:Netherlands; D017063:Outcome Assessment, Health Care; D010570:Pessaries / Q000191:economics; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011272:Pregnancy, Multiple; D047928:Premature Birth / Q000517:prevention & control*; D012107:Research Design; D016896:Treatment Outcome; D014427:Twins