Maternal factors, fetal parameters and the risk of shoulder dystocia

Introduction. Shoulder dystocia is a serious complication of vaginal birth, with an incidence ranging from 0.15% to 2.1% of all births. There are approximately 4 million births per year in the United States and shoulder dystocia will be experienced by approximately 20,000 women each year. Although studies have been reported on shoulder dystocia, few studies have addressed both maternal and fetal risk factors. The purpose of this study was to identify maternal and fetal risk factors for shoulder dystocia while proposing factors that could be used to predict impending shoulder dystocia. Material and methods. Articles were reviewed from Medline Pubmed using the search phrase Risk factors of shoulder dystocia and Medline Ovid using the search words Dystocia , Shoulder and Risk factors . Rigorous selection criteria were used to identify articles to be included in the study. Data collected from identified articles were transferred to STATA 10 software for trend analysis of the incidence of shoulder dystocia and the year of publication and a pair wise correlation was also determined between these two variables. Results. Among a total of 343 studies identified, only 20 met our inclusion criteria and were retained for this review. The incidence of shoulder dystocia ranged from 0.07% to 2% and there was no particular trend or correlation between the incidence of shoulder dystocia and year of publication between 1985 and 2007. Pre-gestational and gestational diabetes, postdatism, obesity, birth weight \u3e 4000g and fundal height at last visit \u3e 40cm were identified as major risk factors in our series of studies. Conclusion. Future strategies to predict shoulder dystocia should focus on pre-gestational and gestational diabetes mellitus, postdatism, obesity, birth weight \u3e 4000g and fundal height at last visit \u3e 40cm