Pessaries for the treatment of incompetent cervix and premature delivery

The purpose of this study was to review published articles about using pessaries in women with an incompetent cervix or who are at risk for preterm delivery. A MEDLINE search was performed from 1966 to 2000, with articles published before 1966 being extracted from the reference lists of articles obtained. Foreign articles were translated into English. Key words included pessary, incompetent cervix, and preterm labor. All studies that included patient data were included. A variety of studies suggest that pessaries can increase the percentage of full-term deliveries when used in women with an incompetent cervix or at risk for preterm delivery. When looking at women thought to have an incompetent cervix, the studies are mostly old case series. One prospective, randomized trial demonstrated no difference between women treated with a pessary and a cerclage. However, 27 weeks was the average gestational age at which therapy was started. In women at risk for preterm delivery, retrospective studies show an increase in full-term pregnancy rates with pessary use. One prospective, nonrandomized study also shows an increase in full-term pregnancy rate. However, in this study, lower risk patients received the pessary. Because of the poor nature of most of the studies, pessaries should not replace cerclage use at this time in women with an incompetent cervix. However, pessary use should be considered as adjuncts to cerclage or in women who are not candidates for cerclage. Also, pessary use may be considered in some women at risk for preterm delivery. Randomized perspective controlled trials are in progress to address the use of pessaries in these situations. Vaginal pessaries have been reported to be useful in women at risk for preterm delivery since 1959. Bedrest and cervical cerclage has become standard therapy in the United States for women with an incompetent cervix. However, cerclage is not without risk. Furthermore, advances in ultrasound have allowed us to identify women potentially at risk for preterm delivery by detecting cervical shortening before dilatation. This ability has raised questions concerning how to manage patients with subtle ultrasound changes. This article reviews the published literature concerning the use of pessaries in women with an incompetent cervix or at risk for early delivery.