PM.25 The Impact of Cervical Surgery on Intervention and Outcome in High Risk Pregnant Women
Background A meta-analysis of 27 studies demonstrated that cervical surgery for cervical intraepithelial neoplasia (CIN) was associated with almost two-fold increased risk of preterm birth (PTB)1. A more recent epidemiological study has suggested no influence of cervical surgery on risk of PTB2. However, rates of intervention were not analysed. The aim of this study was to determine the impact of cervical surgery on intervention and pregnancy outcome in high-risk asymptomatic women.
Methods Analysis of 535 women attending preterm surveillance clinic at St. Thomas’ hospital (1997 to 2011) with a history of one or two previous PTB/mid trimester loss. The rates of spontaneous preterm delivery (<37 weeks’) and interventions were compared in women with and without destructive cervical surgery (DCS).
Results Previous cervical surgery did not significantly increase the risk of a further PTB (13/47 [28%] with history of DCS vs. 122/488 [25%] with no history of DCS, p = 0.68). Women that had previous DCS were significantly more likely to require an ultrasound indicated cerclage compared to those that had no history of DCS (9/47 [19%] vs. 48/488 [10%] respectively; p < 0.05).
Conclusion In this high-risk cohort, DCS increases the risk of intervention, but not the risk of subsequent PTB. Reports suggesting treatment is not a risk factor need to include effects on intervention2. This suggests that cervical surgery may be detrimental to the mechanical function of the cervix and further research to define the role of cerclage in women with prior PTB and DCS is warranted.
Kyrgiou M, Koliopoulos G, Martin-Hirsch P, Arbyn M, Prendiville W, Paraskevaidis E. Obstetric outcomes after conservative treatment for intraepithelial or early invasive cervical lesions: systematic review and meta-analysis. Lancet 2006; 367(9509):489–98
Castanon, A., Brocklehurst, P., Evans, H. et al, Risk of preterm birth after treatment for cervical intraepithelial neoplasia among women attending colposcopy in England: retrospective-prospective cohort study. BMJ 2012;345: 5174.