Postpartum evolution of cervical squamous intraepithelial lesions with respect to the route of delivery.

OBJECTIVE.: To analyze the effect of the mode of delivery on the evolution of cervical squamous intraepithelial lesions. MATERIALS AND METHODS.: A chart review was performed of all pregnant women referred to the Northwestern Memorial Hospital Colposcopy Clinic between January 1990 and December 1998. Postpartum changes in the Pap smear and in a combined cytologic, histologic, and colposcopic impression of cervical status were evaluated. Data were analyzed using the chi, Fisher exact test, or Student t test. RESULTS.: Antepartum cytology was atypical squamous cells of undetermined significance in 23 women (7.1%), low-grade squamous intraepithelial lesions in 226 women (69.3%), and high-grade squamous intraepithelial lesions in 77 women (23.6%). Vaginal delivery occurred in 300 women (92.0%); 6 women (1.8%) had an elective cesarean section, and 20 women (6.1%) underwent a cesarean section after laboring. Of 306 women who had postpartum Pap smears, 37.9% had no change, 58.8% had improvement, and 3.3% had worsening of their cervical cytology. The rates of improvement of postpartum Pap smears were 164/285 (57.5%) following a vaginal delivery and 16/21 (76.2%) after a cesarean section (p = .81). Similarly, using a combined histologic, colposcopic, and cytologic evaluation of the cervix, the route of delivery did not affect postpartum cervical status (p = .68). CONCLUSION.: The route of delivery did not appear to influence the evolution of cervical squamous intraepithelial lesions during pregnancy and the puerperium.