Prediction of risk for shoulder dystocia with neonatal injury

Received 16 January 2006; received in revised form 27 April 2006; accepted 4 May 2006. published online 16 July 2006.

Objective

The purpose of this study was to develop a predictive model of risk for shoulder dystocia (ShD) with injury.

Study design

Medical records in 3 urban university teaching hospitals were reviewed to identify and characterize 498 cases of ShD, including 90 with neonatal injury and a comparison group with of 622 with vaginal delivery (VgD) without ShD. The data were subjected to logistic regression modeling to find the best combination of variables to discriminate between the injury and VgD groups.

Results

The best model included birth weight in combination with maternal height and weight as well as gestational age and parity. A score over 0.5 detected 50.7% of the shoulder dystocia cases with brachial plexus injury along with a false positive rate of 2.7%.

Conclusion

Using a statistical model it is possible to identify adverse combinations of factors that are associated with ShD and neonatal injury along with a relatively low false positive rate.

Key words: Shoulder dystocia, Brachial plexus injury, Prediction

a St Mary's Medical Center

b Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada

c Department of Obstetrics and Gynecology, University of Maryland, School of Medicine, Baltimore, MD

d Department of Obstetrics and Gynecology, The Ottawa Hospital, University of Ottawa, Ottawa, ON, Canada

e Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada

Supported by LMS Medical Systems, Montreal, QC.

Reprints not available from the authors.

PII: S0002-9378(06)00615-6

doi:10.1016/j.ajog.2006.05.013

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