Introduction
Premature delivery is a common complication in twin pregnancies. In singleton pregnancies the chance that a woman will go into labour and deliver before 34 weeks is about 1% but in twin pregnancies the chance of such premature birth is about 13%.
The majority of babies born prematurely survive and develop normally. However, babies born before 34 weeks have a higher chance of dying soon after birth or becoming disabled than babies born at term.
There is some evidence that in singleton pregnancies with a previous premature birth or a short cervix the chances of premature birth may be reduced by them taking progesterone or cervical cerclage. However, randomized studies in twin pregnancies have reported that progesterone does not reduce the risk of premature birth and cervical cerclage increases the risk so these are not recommended.
There is some evidence that in women with twin pregnancies the use of a vaginal pessary reduces the chances of premature birth but the evidence is weak and therefore this issue needs further investigation.
The Fetal Medicine Foundation is conducting a multicentre study in several countries to determine if in twin pregnancies the insertion of a vaginal pessary reduces the chances of premature birth.
Vaginal silicone pessary

