Loop Electrosurgical Excision Procedure (LEEP) is a commonly performed procedure for the treatment of cervical dysplasia in the U.S., with an estimated 59,000 such procedures per year. Despite the fact that this procedure is common and is performed usually on women of reproductive age (given the age distribution of cervical dysplasia), there are few data on the potential impact of this procedure on subsequent pregnancy. Given the established relationship between the length of the cervix and preterm birth, it is plausible that LEEP may increase the risk of preterm birth and other adverse pregnancy outcomes. Thus, the aim of this proposal is to perform the largest observational study of the association between LEEP and preterm birth <34 weeks. We propose a retrospective cohort study, including women from 9 hospitals (community and tertiary) in the Delaware Valley. Women exposed to LEEP (""""""""exposed""""""""), women who have had a cervical punch biopsy without LEEP, and women with neither a LEEP nor punch biopsy (2 unexposed groups) will be ascertained by computerized, hospital specific pathology databases. Subjects will be tracked and contacted via phone, at which time patients will be enrolled into the study. The medical records of all pre and post-LEEP and punch biopsy pregnancies will be obtained and reviewed by trained abstractors. The primary outcome for this study will be the occurrence of a spontaneous preterm birth <34 weeks (since these are most clinically relevant in terms of morbidity and mortality). Secondary outcomes of interest include preterm birth using other definitions (<37 weeks, <28 weeks), spontaneous miscarriage, midtrimester pregnancy loss, and length of gestation. We will also whether characteristics of the LEEP (depth, width) are associated with preterm birth <34 weeks. The analytic plan will include bivariate and multivariate techniques, and the development of a clinical prediction rule. This study will allow for optimal counseling of the many reproductive-aged women who have had LEEP about the impact on pregnancy, and may pave the way for future interventional studies of how best to manage LEEP-exposed women in a subsequent pregnancy.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
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Special Emphasis Panel (ZRG1-HOP-D (02))
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Kasten-Sportes, Carol H
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Washington University
Obstetrics & Gynecology
Schools of Medicine
Saint Louis
United States
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Stout, M J; Frey, H A; Tuuli, M G et al. (2015) Loop electrosurgical excision procedure and risk of vaginal infections during pregnancy: an observational study. BJOG 122:545-51
Frey, Heather A; Stout, Molly J; Odibo, Anthony O et al. (2013) Risk of cesarean delivery after loop electrosurgical excision procedure. Obstet Gynecol 121:39-45
Conner, Shayna N; Cahill, Alison G; Tuuli, Methodius G et al. (2013) Interval from loop electrosurgical excision procedure to pregnancy and pregnancy outcomes. Obstet Gynecol 122:1154-9