978 Cerclage versus vaginal progesterone in low risk pregnant women with a short cervix

Abstract

To compare vaginal progesterone to cerclage in preventing preterm birth and adverse perinatal outcomes in women with a singleton gestation, incidentally found sonographic cervical length of <15 mm, and no history of preterm birth. A retrospective cohort study was conducted on 68 women who delivered at the University of Kansas Health System with a singleton gestation found to have a cervical length <15 mm on transvaginal ultrasound and no history of preterm birth. Women treated with vaginal progesterone (n=29) were compared to women who underwent cerclage placement (n=39). The primary outcome was the difference in average latency period. Secondary outcomes include preterm birth < 37, <34, and <28 weeks, and neonatal morbidities. Of the 268 patients who had a cervical length of <15 mm on transvaginal ultrasound, 68 participants met inclusion criteria and were included in the final analysis. Twenty-nine participants received vaginal progesterone and 39 participants received cervical cerclage. The average cervical length at initiation of therapy was greater in the progesterone cohort (10.5 mm vs 8.0 mm, p<0.01). All other baseline characteristics were similar between groups, including no difference in average gestational age at initiation of therapy (21.6 weeks vs. 21.5 weeks, p=0.87). Average latency after therapy did not differ between groups (100 days vs. 92.7 days p=0.43). The incidence of preterm birth at <37 weeks (41.4% vs. 51.3%), <34 weeks (27.6% vs. 35.9%), and <28 weeks (10.3% vs. 18%), did not differ significantly between groups. Additionally, no difference in neonatal morbidity was detected. At our institution we found no difference between vaginal progesterone and cerclage in the average latency period or risk of preterm birth among women with an incidental short cervix of < 15 mm and no history of preterm birth, despite the significantly shorter initial cervical length in the cerclage group. These findings suggest either vaginal progesterone or cerclage could be used to reduce the risk of preterm birth among this high risk population.View Large Image Figure ViewerDownload Hi-res image Download (PPT)