Reducing the Risk of Shoulder Dystocia and Associated Brachial Plexus Injury Edith D. Gurewitsch, MD a, *, Robert H. Allen, PhD b The current American College of Obstetricians and Gynecologists (ACOG) and Royal College of Obstetricians and Gynecologists (RCOG) guidelines for shoulder dystocia, which were published in 2002 and 2005, respectively, offer useful guidelines for clini- cians about shoulder dystocia incidence, risk factors, prevention, and management. 1,2 Considerable research on shoulder dystocia and its related injuries, some of it contro- versial, has been published on the topic since that time. In this review, the authors summarize some of the recent developments concerning incidence, risk factors, prevention, and management that may be useful to consider in future ACOG and RCOG guidelines. Despite studies that suggest otherwise, considerable evidence can be found to recommend guidelines and interventions that would improve clinical practice and patient outcomes. The objective of this review is to offer health care providers infor- mation, practical direction, and advice on how to limit shoulder dystocia risk and, more importantly, to reduce anoxic and brachial plexus injury risk. The authors review such areas of controversy as prior shoulder dystocia and reducing recur- rence, monitoring and counseling about maternal weight and weight gain during pregnancy to control macrosomia incidence, ultrasonographic assessment of fetal growth to detect asymmetric accelerated truncal growth and/or macrosomia, screening for glucose intolerance and maintenance of target glycemic control to reduce adverse pregnancy outcome (including shoulder dystocia), use of operative delivery in at-risk patients, a safe head-to-body interval, the etiology and natural a Departments of Gynecology and Obstetrics and Biomedical Engineering, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Phipps 217, Baltimore, MD 21287, USA b Departments of Gynecology and Obstetrics and Biomedical Engineering, Johns Hopkins University School of Medicine, 3400 North Charles Street, Clark 118C, Baltimore, MD 21208, USA * Corresponding author. E-mail address: egurewi@jhmi.edu KEYWORDS  Shoulder dystocia  Brachial plexus  Injury  Delivery Obstet Gynecol Clin N Am 38 (2011) 247–269 doi:10.1016/j.ogc.2011.02.015 obgyn.theclinics.com 0889-8545/11/$ – see front matter Ó 2011 Elsevier Inc. All rights reserved.