1. National Collaborating Centre for Women's and Children's Health on behalf of the National Institute for Health and Clinical Evidence (NICE) Induction of Labour 2008 http://guidance.nice.org.uk/CG70/ Guidance/pdf/English
2. Births: final data for 2004;Martin;Natl Vital Stat Rep,2006
3. ACOG Practice Bulletin No. 107. Induction of labor;American College of Obstetricians and Gynecologists;Obstet Gynecol,2009
4. Rising rates of obstetric interventions: exploring the determinants of induction of labour;Humphrey;J Public Health (Oxf),2009
5. Pelvic scoring for elective induction;Bishop;Obstet Gynecol,1964