Cesarean Delivery Changes the Natural Position of the Uterus on Transvaginal Ultrasonography.

OBJECTIVES: To assess whether cesarean delivery changes the natural position of the uterus. METHODS: In this retrospective Institutional Review Board-approved cohort study, we conducted a search of our university gynecologic ultrasonography (US) database. Patients with transvaginal US images before and after either vaginal or cesarean delivery between 2012 and 2015 were included. Women with prior cesarean delivery were excluded. Two readers independently measured antepartum and postpartum flexion angles between the longitudinal axis of the uterine body and the cervix. We calculated intraclass correlation coefficients to measure inter-reader agreement. Antepartum and postpartum uterine flexion angles were compared between patients with vaginal and cesarean delivery. RESULTS: We included 173 patients (107 vaginal and 66 cesarean delivery). The mean interval between scans ± SD was 18 ± 10 months. Inter-reader agreement for flexion angles was almost perfect (intraclass correlation coefficients: antepartum, 0.939; postpartum, 0.969; both P < .001). There was no difference in mean antepartum flexion angles for cesarean delivery (154.8° ± 45.7°) versus vaginal delivery (145.8° ± 43.7°; P = .216). Mean postpartum flexion angles were higher after cesarean delivery (180.4° ± 51.2°) versus vaginal delivery (152.8° ± 47.7°; P = .001. Differences in antepartum and postpartum flexion angles between cesarean and vaginal delivery were statistically significant (25.6° versus 7.0°; P = .027). CONCLUSIONS: Cesarean delivery can change the uterine flexion angle to a more retroflexed position. Therefore, all women with a history of cesarean delivery should undergo a transvaginal US examination before any gynecologic surgery or intrauterine device placement to reduce the possibility of surgical complications.

Factors associated with cesarean delivery rates: a single-institution experience.

BACKGROUND: The aim of this study was to identify factors associated with variability in Cesarean delivery (CD) rates amongst providers at a single institution. METHODS: A retrospective cohort analysis was carried out on all births at NYU Langone Medical Center from 2005-2013. Data was collected for subjects and linked to diagnosis codes for singleton and twin deliveries. Descriptive characteristics were generated for all deliveries, and inferential analysis was performed including multiple covariates for singleton deliveries in the 2010-2013 cohort, including both univariate and multivariate regression analyses to identify factors associated with higher CD rates. RESULTS: 37,692 deliveries were identified at our institution during the study period, performed by 88 unique providers. The mean CD rate was 29.6%, with a range for individual physicians from 9.9% to 75.6%. In multivariate regression analysis, CD rate was directly correlated with average patient age, physician male gender, proportion of high-risk deliveries, and Maternal-Fetal Medicine specialty, and it was inversely correlated with total number of deliveries by physician and forceps delivery rate. There was no significant difference in CD rates between group and solo practices. Within the same group practice, each member's CD rate was strongly correlated with the average CD rate of the group. CONCLUSION: Our study demonstrates the wide range of CD rates for providers practicing within the same institution and reiterates the association of CD rates with patient age, high-risk pregnancy, and provider volume. Among operative vaginal deliveries, forceps delivery rate was associated with lower CD rates whereas vacuum delivery rate was not. Despite these findings, practice patterns within individual practices appear to contribute significantly to the wide range of CD rates.