1. Cervical stitch (cerclage) for preventing pregnancy loss in women;Drakeley;Cochrane Database Syst Rev,2003
2. Prenatal administration of progesterone for preventing preterm birth in women considered to be at risk of preterm birth;Dodd;Cochrane Database Syst Rev,2006
3. Cervical stitch (cerclage) for preventing preterm birth in singleton pregnancy;Alfirevic;Cochrane Database Syst Rev,2012
4. Prenatal administration of progesterone for preventing preterm birth in women considered to be at risk of preterm birth;Dodd;Cochrane Database Syst Rev,2013