Trends over Time and Factors Associated with Episiotomy for Vaginal Births in New York State

ABSTRACT: Background: The American College of Obstetricians and Gynecologists recommends restricted use of episiotomies. Evidence has shown that routine use of episiotomies is not beneficial and can lead to greater postpartum discomfort. The purpose of this study is to identify factors associated with episiotomies and determine if these factors are changing over time.

Methods: Maternal data from New York State's (NYS) hospital discharge database for 1993-2002 were included (data for 2003 to 2007 will be added for the presentation). Episiotomies were identified by an ICD-9-CM procedure code of 73.6. This study included deliveries by NYS residents who were HIV negative and had a non-emergent vaginal, singleton birth. Log-binomial regression analysis, stratified by regions of NYS, was utilized to determine the association between episiotomy with multiple available factors (e.g., insurance (private vs. public), age, and race/ethnicity).

Results: Of 1,176,561 deliveries meeting study criteria, overall 28.8% had episiotomies, declining from 38.0% in 1993 to 18.5% in 2002. In 2002, the interquartile range of episiotomies by individual hospital was 8.2% - 25.7%, with negligible differences between teaching hospitals (median=18.6%) and non-teaching hospitals (median=18.4%).

Based on regression analysis for NYS outside NYC, private insurance was the strongest factor associated with episiotomy procedures, adjusted for other factors. This association varied by age, and was strongest for women 35 or older, the relative risk for these women was 2.3 (95% CI 2.2-2.4) for private compared to public insurance; for the 18-34 age group the relative risk was 1.61 (95% CI 1.60-1.63). Among deliveries covered by private insurance the frequency of procedures did not vary by age, however for the publicly insured, women under 18 had the most episiotomies (28.4%), followed by women 18-34 (19.5%) and older women (13.0%). For both private and public insurance, Hispanics had the highest frequency of episiotomies, followed by whites, and blacks had the lowest. These associations were consistent throughout the study period with only minor changes in relative risks between 1993 and 2002. Adjusting for delivery of large babies did not alter these findings. Results were similar for NYC, except there was more variation based on age within private and public insurance.

Conclusion: Future research is necessary to understand how insurance type may impact guideline appropriate care of pregnant women. Wide variation of episiotomy frequency across hospitals, both teaching and non-teaching, and race/ethnic disparities suggests that opportunities for identifying positive deviants to learn about best practices exist.