Pathophysiology & Risk Factors

Uterine rupture is a catastrophic full-thickness tearing of the uterine wall, most often at a previous cesarean scar during a trial of labor after cesarean (TOLAC/VBAC). Once wall integrity is lost the uterus can no longer contract, the fetal presenting part may recede, and blood pools intraperitoneally producing concealed hemorrhage. A complete rupture communicates with the peritoneal cavity and is a surgical emergency; an incomplete rupture (dehiscence) leaves the serosa intact and may show only subtle FHR changes.

Rupture risk by prior uterine scar

Scar typeApprox. rupture rate

Classical (vertical) incisionHighest risk~4-9%

Low transverse incisionLower risk~0.5-1%

Scar type

Classical (vertical) incision: Highest risk
Low transverse incision: Lower risk

Approx. rupture rate

Classical (vertical) incision: ~4-9%
Low transverse incision: ~0.5-1%

Signs & Symptoms

EarlyProgresses →

sudden sharp tearing abdominal pain Hallmark

client may report "something ripped"; blunted by epidural

abrupt cessation of contractions Hallmark

disrupted myometrium can no longer contract

prolonged fetal bradycardia Hallmark

uteroplacental perfusion acutely lost

loss of fetal station

presenting part recedes upward

Late / Severe

palpable fetal parts through abdomen

fetal extrusion through uterine defect

maternal tachycardia

compensatory sign of hemorrhagic shock

maternal hypotension

referred shoulder pain

diaphragmatic irritation from intraperitoneal blood

Diagnostics & Labs

Diagnostic

clinical triad recognition Hallmark

pain + loss of contractions + fetal bradycardia; rupture is a clinical diagnosis

type and crossmatch

Monitor

continuous fetal heart rate monitoring

tocodynamometer contraction tracing

shows abrupt loss of pattern

CBC

trend hemoglobin/hematocrit for blood loss

Interventions & Priorities

Suspected complete rupture — first actions

Recognize triadpain + no contractions + fetal bradycardia
Stop oxytocinhalt uterine stimulation
Activate surgical teamcall for emergency cesarean
Resuscitate2 large-bore IVs, fluids, O2, blood ready
Emergency cesareandelay >10-15 min worsens outcomes

Treatments & Medications

emergency cesarean delivery Hallmark

definitive treatment

surgical uterine repair

if defect repairable

hysterectomy

if hemorrhage uncontrolled

blood transfusion

for hemorrhagic shock

Patient Teaching

report sudden severe abdominal pain

during TOLAC/VBAC labor

understand TOLAC rupture risk

informed consent for trial of labor after cesarean

report decreased fetal movement

Complications

maternal hemorrhagic shock

fetal hypoxic injury

fetal death

emergency hysterectomy

Report Nowescalate immediately

sudden tearing abdominal pain Hallmark

cessation of contractions Hallmark

abrupt fetal bradycardia Hallmark

loss of fetal station

palpable fetal parts through abdomen

maternal hemodynamic collapse

signs of hemorrhagic shock from concealed bleeding

Clinical Pearl

Pain then silence: if a laboring VBAC client screams in pain and contractions vanish from the monitor, think rupture until proven otherwise.

Uterine Rupture