Indications for and pregnancy outcomes of cervical cerclage: 11-year comparison of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage

Objectives To review and compare pregnancy outcomes of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage. Design Case series with internal comparison. Setting A regional obstetric unit in Hong Kong. Patients Women undergoing cervical cerclage at Kwong Wah Hospital between 1 January 2001 and 31 December 2011. Interventions Cervical cerclage. Main outcome measures Pregnancy outcomes including miscarriage, gestational age at delivery, birth weight, and duration of pregnancy prolongation. Results Overall, 47 patients were included. Nine (19.1%) pregnancies resulted in miscarriage. The median gestational age at delivery was 35.7 weeks. Among the 23 patients who had history-indicated cerclage, only four (17.4%) had three or more previous second-trimester miscarriages or preterm deliveries. Among the 15 patients who had ultrasound-indicated cerclage, preoperative cervical length of ≤1.5 cm was associated with shorter prolongation of pregnancy, compared with that of >1.5 cm (median, 12.1 vs 18.4 weeks; P=0.009). Among the nine women who had rescue cerclage, those who underwent the procedure before 20 weeks of gestation delivered earlier than those underwent cerclage later (median, 22.5 vs 34.1 weeks; P=0.048). Conclusions Patients eligible for the Royal College of Obstetricians and Gynaecologists-recommended history-indicated cerclage remain few. The majority of patients may benefit from serial ultrasound monitoring of cervical length with or without ultrasound-indicated cerclage.