(672) Outcomes of operative vaginal deliveries by hospital volume status

It is unknown whether outcomes after operative vaginal delivery (OVD) differ by hospital characteristics, such as volume of operative vaginal deliveries in a hospital. Therefore, we sought to assess whether outcomes after OVD differ significantly between hospitals of different volumes of OVD. 

Study Design:

This was a retrospective cohort study of singleton, non-anomalous, term deliveries in California between 2007 and 2019. We stratified hospitals into three categories based on proportion of OVD among all deliveries; the categories were low volume (< 5%), medium volume (5-7%) and high volume (≥7%). Chi-squared and multivariable logistic regression analyses were utilized to assess an association between OVD and adverse perinatal outcomes, among three hospital volumes separately.

Results:

In this study, we included 4,629,808 births, of which 31.7% were in low volume hospitals, 34.8% in medium-volume and 33.5% in high volume hospitals. Among low volume hospitals, OVD were associated with higher odds of obstetrics anal sphincter injuries (aOR=5.85 (5.68, 6.03)), cervical lacerations (1.33 (1.13, 1.56)), postpartum hemorrhage (1.21 (1.17, 1.26)), shoulder dystocia (3.81 (3.63, 4.00)), Apgar scores of < 7 at 5 minutes (1.92 (1.80 , 2.06)), NICU admissions (1.35 (1.31, 1.39)), facial nerve palsy (4.68 (3.18, 6.91)), scalp birth injuries (3.96 (3.85, 4.08)), and brachial plexus injury (5.07 (4.38, 5.87)). Medium-volume and high-volume hospitals had similar higher odds of perinatal outcomes too. 

 

Conclusion:

We found that obstetric outcomes were similar among births via OVD at hospitals of differing volumes. These findings illustrate the importance of ensuring providers at hospitals of all sizes are trained in operative deliveries, as low-volume settings can have outcomes consistent with hospitals of medium and high volumes.