The impact of cervical dilatation on pregnancy outcomes after cerclage placement in women with a short cervical length

Objective: The aim of the study was to compare the outcome of pregnancies with cerclage placement in which cervical length was <15 mm and 15-25 mm. We further investigated the impact of cervical dilatation on delivery at <34 weeks. Material and Methods: Women with singleton gestations with cerclage placement due to cervical insufficiency were enrolled into the study. The data were collected prospectively between September 2004 and February 2009. We divided patients into two categories: (group I) cervical length below 15 mm, (group II) cervical length between 15-25 mm. We compared the pregnancy outcomes of the two groups and also analyzed the independent impact of cervical dilatation on delivery <34 weeks.Results: The cervical cerclage group <15 mm had a similar incidence of preterm delivery <34 weeks gestation to the cerclage group 15-25 mm (p=0.4). No significant difference in rate of neonatal survival (p=0.6) was found between the two groups. Increased cervical dilatation in centimeters was found to be a significant predictor of delivery before 34 weeks gestation (OR: 3.4, 95% CI: 1.3-8.5, p=0.009). Conclusions: The extent of cervical shortening did not have a significant independent effect on the perinatal outcome of patients with cerclage placement. However, the presence of cervical dilatation prior to cerclage placement in cases of cervical insufficiency may worsen perinatal outcomes by increasing the rate of delivery before 34 weeks.