Cervical Length Following Cerclage Placement in Twin Gestations With Ultrasound Indicated Short Cervix [30S

Abstract

INTRODUCTION: Identification of a short-cervix during transvaginal ultrasound in the second-trimester is associated with an increased risk of spontaneous preterm birth (sPTB) in singleton pregnancies. Ultrasound indicated cerclage reduces the risk of recurrence in those with a history of sPTB. The utility of cerclage in twin-gestations is less understood. Our objective was to identify the impact of placing a cerclage in women with a twin-gestation and an ultrasound indicated short-cervix <25 mm. METHODS: We performed a descriptive analysis of all twin gestations delivered at a single tertiary care center with ultrasound evaluation between January 1, 2013 and September 1, 2017. Women with missing maternal or neonatal data were excluded. Outcomes of interest included midtrimester transvaginal cervical length (CL), the effect of cerclage placement on subsequent measurements and gestational age (GA) at delivery. IRB approval was obtained. RESULTS: Of 587 twin pregnancies, 26 patients were diagnosed with a short-cervix and received a cerclage. After placement, an average increase in CL of 7.4 mm at the first CL follow-up (P=.002) and remained significant during subsequent follow-ups. Average GA at delivery was significantly earlier for patients with a CL <15 mm compared to patients with a CL >15 mm; 33 weeks and 4-days versus 35 weeks and 4-days respectively (P=.003). CONCLUSION: Cerclage placement significantly increases transvaginal CL following the procedure. While the severity of the short-cervix appears to predict earlier GA at delivery it remains unclear if cerclage placement alters the GA at delivery. CL monitoring following the placement of a cerclage has unknown clinical benefit after cerclage placement in twin-gestations.