Learning objectives

• Description of a uterine rupture
• Management of a uterine rupture

Definition and mechanisms

• Uterine rupture refers to a complete division of all three layers of the uterus: the endometrium (inner epithelial layer), myometrium (smooth muscle layer), and perimetrium (serosal outer surface)
• Typical rupture occurs during labor, but it may occasionally happen earlier in pregnancy
• The fetus is left without the protection of the uterus, leaving the fetus without oxygen and causing the fetus’s heart rate to slow down
• Suspect uterine rupture based on a rapid drop in the baby’s heart rate during labor
• The cardinal sign of uterine rupture is loss of fetal station on a manual vaginal exam
• The maternal mortality rate is < 1%, fetal mortality rate is between 2-6 %
• Incomplete rupture:
  • Peritoneum is still intact
• Complete rupture:
  • All three layers are ruptured
  • The contents of the uterus spill into the peritoneal cavity or the broad ligament
• Bladder injury is not uncommon with uterine rupture
• A caesarean section is recommended in women who have had a prior rupture

Signs and symptoms

• Vaginal bleeding
• Abdominal pain and tenderness
• Chest pain, pain between the scapulae, or pain on inspiration
• Hypovolemic shock
• Signs associated with fetal oxygenation:
  • Late deceleration
  • Reduced variability
  • Tachycardia
  • Bradycardia
• Absent fetal heart sounds
• Cessation of uterine contractions
• Palpation of the fetus outside the uterus (usually occurs only with a large, complete rupture)

Risk factors

• History of uterine surgery
• Previous uterine rupture
• Uterine trauma
• Congenital uterine anomalies such as septate uterus or bicornuate uterus
• Vaginal birth after caesarean section
• Trauma
• Cocaine use
• Stretch uterus (multiples or too much amniotic fluid)
• A breech position requiring external cephalic version
• Pronged labor

Complications

Diagnosis

• Laboratory tests:
  • Hemoglobin or hematocrit
  • Coagulation tests (prothrombin time, activated partial thromboplastin time, fibrinogen, thromboelastogram)
• Ultrasound 
  • To rule out placenta praevia, placental abruption, or spontaneous abortion
  • To support the diagnosis: abnormality in the uterine wall, a hematoma next to hysterotomy scar, free fluid in the peritoneum, anhydramnios or fetal parts outside the uterus

Management

Suggested reading

• Gibbins KJ, Weber T, Holmgren CM, Porter TF, Varner MW, Manuck TA. Maternal and fetal morbidity associated with uterine rupture of the unscarred uterus. Am J Obstet Gynecol. 2015;213(3):382.e1-382.e3826.
• Plaat F, Shonfeld A. 2015. Major obstetric haemorrhage. BJA Education. 15;4:190-193.
• Walfish M, Neuman A, Wlody D. 2009. Maternal haemorrhage. BJA:: British Journal of Anaesthesia. 103;1:47-56.
• Guiliano M, Closset E, Therby D, LeGoueff F, Deruelle P, Subtil D. Signs, symptoms and complications of complete and partial uterine ruptures during pregnancy and delivery. Eur J Obstet Gynecol Reprod Biol. 2014;179:130-134.