Drife J. The start of life: a history of obstetrics. Postgrad Med J 2002;78:311–5.NHS Maternity Statistics.Murphy DJ, Liebling RE, Verity L, Swingler R, Patel R. Early maternal and neonatal morbidity associated with operative delivery in second stage of labour: a cohort study. Lancet 2001;358:1203–7 [Abstract only].Royal College of Obstetricians and Gynaecologists. Operative vaginal delivery. Green-top Guideline 26. London: RCOG Press; 2011.
