Prevention of Preterm Birth With a Pessary in Twin Gestations

Preterm birth (PTB) is a major health problem and contributes to more than 50% of the overall perinatal mortality. Twins are at increased risk for PTB. The number of twins births has risen substantially due to the increased use of assisted reproductive technology. The rate of twin births in the United States rose from 18.9 to 32.2 per 100 live births between 1980 and 2004. The increased rate of PTB in twins is associated with increased morbidity and mortality rates. Almost one in four very low birth-weight infants (below 1500 g) born in the United States are twins, as are one in six infants who die in the first month of life. Cervical shortening is a risk factor for PTB. Transvaginal ultrasound measurement of cervical length is a reliable screening test for prediction of PTB. There is currently no effective treatment to decrease the incidence of PTB in women with twin gestations, but there is some evidence that the use of a cervical pessary in women with a short cervix has promise. If effective this approach would be particularly appealing because of the wide availability of pessaries, ease of use, and low cost. Unfortunately, existing studies are inadequate to confirm effectiveness; a well designed, properly powered, prospective randomized trial is warranted prior to widespread implementation in clinical practice. We propose such a trial to study the effectiveness of the pessary in decreasing the incidence of PTB in an inner city Philadelphia population.