title: Tocogram characteristics of uterine rupture: a systematic review.
abstract: OBJECTIVE
  Timely diagnosing a uterine rupture is challenging. Based on the pathophysiology of complete uterine wall separation, changes in uterine activity are expected. The primary objective is to identify tocogram characteristics associated with uterine rupture during trial of labor after cesarean section. The secondary objective is to compare the external tocodynamometer with intrauterine pressure catheters.
  
  
  METHODS
  MEDLINE, EMBASE, and the Cochrane library were systematically searched for eligible records. Moreover, clinical guidelines were screened. Studies analyzing tocogram characteristics of uterine rupture during trial of labor after cesarean section were appraised and included by two independent reviewers. Due to heterogeneity, a meta-analysis was only feasible for uterine hyperstimulation.
  
  
  RESULTS
  Thirteen studies were included. Three tocogram characteristics were associated with uterine rupture. (1) Hyperstimulation was more frequently observed compared with controls during the delivery (38 versus 21 % and 58 versus 53 %), and in the last 2 h prior to birth (19 versus 4 %). Results of meta-analysis: OR 1.68 (95 % CI 0.97-2.89), p = 0.06. (2) Decrease of uterine activity was observed in 14-40 % and (3) an increasing baseline in 10-20 %. Five studies documented no changes in uterine activity or Montevideo units. A direct comparison between external tocodynamometer and intrauterine pressure catheters was not feasible.
  
  
  CONCLUSIONS
  Uterine rupture can be preceded or accompanied by several types of changes in uterine contractility, including hyperstimulation, reduced number of contractions, and increased or reduced baseline of the uterine tonus. While no typical pattern has been repeatedly reported, close follow-up of uterine contractility is advised and hyperstimulation should be prevented.
authors.affiliation: Department of Obstetrics and Gynecology, Máxima Medical Center, P.O. Box 7777, 5500 MB, Veldhoven, The Netherlands. marionvlemminx@hotmail.com.|Department of Electrical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands. marionvlemminx@hotmail.com.
authors.forename: Marion W C
authors.initials: MW
authors.lastname: Vlemminx
authors.affiliation: Department of Obstetrics and Gynecology, Máxima Medical Center, P.O. Box 7777, 5500 MB, Veldhoven, The Netherlands.|Department of Electrical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
authors.forename: Hinke
authors.initials: H
authors.lastname: de Lau
authors.affiliation: Department of Obstetrics and Gynecology, Máxima Medical Center, P.O. Box 7777, 5500 MB, Veldhoven, The Netherlands.|Department of Electrical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
authors.forename: S Guid
authors.initials: SG
authors.lastname: Oei
mesh_terms: D005260:Female; D006801:Humans; D011247:Pregnancy; D011312:Pressure; D014219:Trial of Labor; D014590:Uterine Contraction / Q000502:physiology; D018590:Uterine Monitoring; D014597:Uterine Rupture / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D016064:Vaginal Birth after Cesarean / Q000009:adverse effects*
keywords: External tocodynamometer; Hyperstimulation; Intra-uterine pressure catheter; Tocogram; Trial of labor after cesarean section; Uterine rupture