Loop electrosurgical excision of the cervix and risk for spontaneous preterm delivery in twin pregnancies.

OBJECTIVE

To investigate the association between three cervical procedures (biopsy with no treatment, ablation, and loop electrosurgical excision procedure [LEEP]) and subsequent spontaneous preterm delivery in twin pregnancies using population-based data from various nationwide registries.

METHODS

: The study population consisted of all twin deliveries in Denmark during a 9-year period, 1997-2005. Information on the deliveries, including cervical procedures, was obtained from various national registries. In all, 9,868 deliveries were eligible for analyses, of which 3,228 were delivered spontaneously preterm (32.7%). Preterm delivery was defined as gestational age between 21 weeks and 37 weeks. Logistic regression analyses were used to evaluate the association between cervical procedures and preterm delivery.

RESULTS

Twin pregnancies subsequent to LEEP had a significantly increased risk of overall subsequent spontaneous preterm delivery (43.4%) with an adjusted odds ratio of 1.58 (95% confidence interval 1.16-2.14) compared with pregnancies with no prior LEEP (32.5%). The association was consistent in various secondary analyses and especially strong for the very preterm and extremely preterm groups. We found no increase in risk of preterm delivery subsequent to biopsy without treatment or ablation.

CONCLUSION

Our study showed an overall significant increase in risk of preterm delivery in twin pregnancies subsequent to LEEP treatment, even after adjustment for several potential risk factors.

LEVEL OF EVIDENCE: II.