Poster session II Diabetes, labor, medical-surgical-disease, obstetric quality & safety, prematurity, ultrasound-imaging: Abstracts 237 – 386| Volume 206, ISSUE 1, SUPPLEMENT , S145-S146, January 01, 2012

304: Shoulder dystocia: risk factors and outcomes in 453 consecutive cases


      Shoulder dystocia (SD) is an uncommon and unpredictable event complicating 0.2–3% of all vaginal deliveries. We sought to examine the current risk factors and perinatal outcome of all cases of shoulder dystocia in a single institution over a six year period.

      Study Design

      This is a prospective observational study carried out at a large tertiary referral center serving a single urban population over a 6 year period from 2005-2010. Shoulder dystocia was defined as failure to deliver the shoulders at the first attempt in singleton cephalic vaginal deliveries. Details of maternal demographics, intrapartum characteristics and neonatal outcomes were recorded prospectively on a computerized database for analysis.


      During the study period there were 51,919 deliveries and 453 cases of SD, giving an incidence of 8.7/1000 births. The mean maternal age was 30.8 +/− 5.3 years. Almost 70% (n=311) occurred at a gestation of greater than 40 weeks. The majority of cases of SD (69%, 312/453) occurred following spontaneous onset of labor. The mean birthweight was 4187g (2920-5780g). Twenty-four babies (5.7%) had an Apgar score of less than 7 at 5 minutes, and 21 (4.6%) had a cord pH < 7.1. In total 61 babies (13.5%) required admission to the neonatal unit. 30 women (6.6%) suffered anal sphincter injury and 20.8% had blood loss of greater than 500ml at delivery. There were 83 cases of Erbs palsy (18%) the vast majority of which resolved spontaneously and 5 cases of hypoxic ischemic encephalopathy (2 mild, 3 moderate).


      We consider this robust and significant data relating to contemporary antecedents and outcomes of SD. As a complication which carries a significant risk of persistent neurological injury for the infant and consequent medicolegal implications for the clinician, continuous audit and high levels of awareness and training for all birth attendants should now be standard practice.