Pregnancy outcome after loop electrosurgical excision procedure: a systematic review

OBJECTIVE: To examine the association of loop electrosurgical excision procedure (LEEP) and subsequent pregnancy outcomes. DATA SOURCES: A computerized search of MEDLINE and PubMed was conducted using the keys words "pregnancy" and "loop electrosurgical excision procedure," "LEEP," "LETZ," "LLETZ," or "loop excision." References from identified publications were manually searched and cross referenced to identify additional relevant articles. METHODS OF STUDY SELECTION: Studies were included that compared women who had had LEEP to women who had not had the procedure and that reported on subsequent pregnancy outcomes. Studies were excluded if there was no control group, if the LEEP was performed during the pregnancy, or if only an abstract was available. Five of 36 articles identified met the criteria for systematic review. TABULATION, INTEGRATION, AND RESULTS: Women who had had LEEP were more likely to have preterm birth (odds ratio OR 1.81, 95% confidence interval CI 1.18, 2.76; P = .006) and low birth weight infants (<2500 g) (OR 1.60, 95% CI 1.01, 2.52; P = .04), but there was no difference in cesarean delivery, precipitous labor, labor induction, or neonatal intensive care unit admission. A subgroup analysis including only studies matching for smoking status revealed that preterm birth was still more common in women who had had LEEP (OR 2.53, 95% CI 1.42, 4.49; P = .001), but birth weight under 2500 g was no longer significantly different. CONCLUSION: LEEP appears to be associated with subsequent preterm birth, even when smoking status is matched. Studies with adequate sample size are needed to further evaluate the relationship of LEEP and preterm birth, controlling for potential confounders, including depth of the tissue sample.