826 Does the mode of delivery influence the natural history of untreated cervical intraepithelial neoplasia?

Abstract

Introduction/Background* Abnormal cervical cytology has been reported in approximately 5% of pregnancies. Dynamic cervical changes produced during labor and vaginal delivery such as dilation, epithelial desquamation and immunologic/repair processes can be associated with higher regression rates of cervical intraepithelial (CIN) lesions. However, the published literature reveals heterogeneous data and controversial results about this effect.The objective of this study is to evaluate the influence of the mode of delivery on the histologic regression, persistence and progression rates of CIN. Methodology A retrospective cohort study including all patients who gave birth in Hospital del Mar (Barcelona, Spain) during 2015 and 2016 was performed, identifying patients with an abnormal cervical cytology previous to delivery. Subjects were required to have postpartum follow-up that included cervical cytology between 2-9 months postpartum.The test used was liquid-based cytology and abnormal results were classified in atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (L-SIL), high-grade squamous intraepithelial lesion (H-SIL) and atypical glandular cells (ACG).The evolution of lesions is evaluated according to whether regression, stability or progression occurs. Rates of regression and progression of cervical lesions according to the mode of delivery (vaginal vs cesarian section) were compared. Statistical analysis was performed by Chi-square test. Result(s)* Data from 2586 pregnant women was revised, finding 197(7.6%) women with abnormal cytology, of which 122 women met inclusion criteria, 85(69.7%) delivered vaginally and 37(30.3%) by cesarean section. Regression occurred in 56 (65.9%) patients with vaginal delivery and in 28(75.7%) with cesarean section (p=0.395). Progression occured in 15 cases, 8(10.5%) delivered vaginally and 7(18.9%) by cesarean section (p=0.228).The global regression rate was 69.2% for H-SIL, 63.5% for L-SIL and 75% for ASCUS. None of H-SIL progressed to invasive carcinoma and only one case of ACG resulted into H-SIL in postpartum. Conclusion* In the group of patients studied, there are no differences in the rates of regression or progression of cervical lesions depending on whether they have a vaginal delivery or cesarean section.This study reports a high regression rates and low progression rates after delivery supporting that a conservative management of CIN during pregnancy is safe.