Nygaard IE, Rao SS, Dawson JD: Anal incontinence after anal sphincter disruption: a 30-year retrospective cohort study. Obstet Gynecol 89:896, 199
O'Callaghan ME, MacLennan AH, Gibson CS, et al: Epidemiologic associations with cerebral palsy. Obstet GynecoIr118(3):576, 2011
O'Mahony F, Hofmeyr GJ, Menon V: Choice of instruments for assisted vaginal delivery. Cochrane Database Syst Rev 11:CD005455, 2010
Osterman MJ, Martin JA, Menacker F: Expanded health data from the new birth certificate, 2006. Nat! Vital Stat Rep 58(5):1, 2009
Palatnik A, Grobman WA, Hellendag MG, et al: Predictors offailed operative vaginal delivery in a contemporary obstetric cohort. Obstet Gynecol 127(3): 501,r2016
Pearl ML, Roberts JM, Laros RK, et al: Vaginal delivery from the persistent occiput posterior position: influence on maternal and neonatal morbidiry. J Reprod Med 38:955, 1993
Pergialiotis V, Vlachos 0, Protopapas A, et al: Risk factors for severe perineal lacerations during childbirth. Int J Gynaecol Obstet 125(1):6,r2014
Pifarotti P, Gargasole C, Folcini C, et al: Acute post-partum urinary retention: analysis of risk factors, a case-control study. Arch Gynecol Obstet 289(6):1249,r2014
Ramphul M, Kennelly MM, Burke G, et al: Risk factors and morbidiry associated with suboptimal instrument placement at instrumental delivery: observational study nested within the Instrumental Delivery & Ultrasound randomised controlled trial ISRCTN 72230496. BJOG 122(4):558,r2015
RobertSon PA, Laros RK, Zhao L: Neonatal and maternal outcome in lowpelvic and mid-pelvic operative deliveries. Am J Obstet Gynecol 162: 1436, 1990
Rorrveit G, Dalrveit AK, Hannestad YS, et al: Urinary incontinence after vaginal delivery or cesarean section. N Engl J Med 348:9000, 2003
Schuit E, Kwee A, Westerhuis ME, et al: A clinical prediction model to assess the risk of operative delivery. BJOG 119(8):915,r2012
Schwartz DB, Miodovnik M, Lavin JP Jr: Neonatal outcome among low birth weight infants delivered spontaneously or by low forceps. Obstet Gynecol 62:283, 1983
Skinner S, Davies-Tuck M, Wallace E, et al: Perinatal and maternal outcomes after training residents in forceps before vacuum instrumental birth. Obstet Gynecol 130(1):151,r2017
Seidman OS, Laor A, Gale R, et al: Long-term efects of vacuum and forceps deliveries. Lancet 337:1583, 1991
Solt I, Jackson S, Moore T, et al: Teaching forceps: the impact of proactive faculry. Am J Obstet Gynecol 204(5):448.e1, 2011