Clinical overview
Uterine rupture is a full-thickness separation of the uterine wall — myometrium and overlying visceral peritoneum (serosa) — that, when complete, opens the uterine cavity into the peritoneal cavity. It is one of the great intrapartum catastrophes: in a matter of minutes it can exsanguinate the mother and asphyxiate the fetus. Because the fetus may be partly or wholly extruded into the abdomen and the placenta separated from its blood supply, the perinatal mortality of complete rupture is high, and maternal death from haemorrhage remains a real outcome where surgical and blood-bank response is slow. For the South African registrar this is not an abstract examination topic. Obstetric haemorrhage is consistently one of the leading direct causes of maternal death reported by the Saving Mothers / NCCEMD programme, and ruptured uterus sits within that bracket — frequently judged avoidable through earlier recognition of obstructed labour, safer use of uterotonics, and timely transfer between levels of care.
The clinical problem is twofold. First, recognition: classic teaching describes sudden severe pain, cessation of contractions, vaginal bleeding, an abnormal fetal heart rate, loss of station and maternal collapse, but in practice the presentation is often insidious, and an abnormal cardiotocograph (CTG) — particularly new fetal bradycardia — is the single most consistent sign. Second, response: rupture is a "decision-to-delivery in minutes" emergency demanding simultaneous maternal resuscitation, massive-haemorrhage activation and immediate laparotomy. In a country where many women labour in district hospitals without on-site obstetricians, blood banks or theatres, the registrar's job is as much about anticipating the high-risk parturient — the woman with a previous caesarean attempting vaginal birth after caesarean, or the multipara in obstructed or oxytocin-augmented labour — as it is about operating once disaster strikes.
Core knowledge
Definitions and a critical distinction
Two entities must be separated because their significance differs enormously:
- Complete (true) uterine rupture — full-thickness disruption of the uterine wall including the visceral peritoneum, communicating with the peritoneal cavity. The fetus, placenta or both may be wholly or partly extruded. This is the surgical emergency.
- Uterine (scar) dehiscence — a "windowing" or separation of a previous scar in which the visceral peritoneum (and often the fetal membranes) remains intact, with no extrusion and frequently little bleeding. Many dehiscences are asymptomatic and found incidentally at repeat caesarean. They are not equivalent to rupture, though a dehiscence can extend into frank rupture during labour.
This distinction matters for counselling, for VBAC decision-making, and for examination answers — conflating the two is a common error.
Pathophysiology
The pregnant uterus ruptures along a line of mechanical weakness or under a load the wall cannot bear. Two dominant mechanisms:
- Rupture through a previous uterine scar. The commonest setting in modern obstetrics. A previous lower-segment caesarean scar is far more resistant than a classical (upper-segment vertical) scar; the upper segment is the contractile, thick, high-tension part of the uterus and a vertical scar there carries a substantially higher rupture risk, classically quoted in the order of a few percent and high enough that classical scars are a contraindication to planned labour. Other scars carry risk too: previous myomectomy (especially if the cavity was breached), prior rupture or dehiscence repair, cornual/interstitial ectopic resection, and uterine perforation.
- Rupture of an unscarred uterus. Less common but often more devastating, and disproportionately important in low-resource settings. The usual substrate is obstructed labour — cephalopelvic disproportion, malposition or malpresentation, a fetal anomaly, or a pathological retraction (Bandl's) ring — where the lower segment thins and finally tears. Layered on this are inappropriate uterotonic use (oxytocin or, dangerously, misoprostol-driven hyperstimulation), high parity (the multiparous uterus is more fragile), prior instrumentation, fundal pressure, internal podalic version, difficult instrumental delivery, and direct trauma (assault, motor-vehicle crash). Placenta percreta invading through the wall is another mechanism.
The final common path in obstructed labour is worth picturing: the upper segment retracts and shortens while the lower segment passively stretches and thins to accommodate the impacted presenting part. The junction between the two — the physiological retraction ring — rises abnormally high and becomes palpable as Bandl's ring, a late, ominous sign of imminent rupture.
Figure J11.1 — Rupture-versus-dehiscence distinction and the two main pathways to rupture: scar failure under stress and obstructed labour with lower-segment thinning and Bandl's ring.
Epidemiology and risk
Rupture of an unscarred uterus is rare in absolute terms, but the population-level rate is heavily driven by the prevalence of previous caesarean and by access to safe intrapartum care. In a planned VBAC labour the risk of scar rupture is classically quoted at roughly 0.5% (about 1 in 200) after a single previous lower-segment caesarean, rising with induction and augmentation of labour — and prostaglandin induction in a scarred uterus is particularly hazardous (treat these figures as standard teaching and confirm exact numbers against current guidance). Factors that raise VBAC rupture risk include short inter-delivery interval, more than one previous caesarean, induced/augmented labour, and a previous caesarean for a recurring indication. See vbac for the full risk–benefit counselling.
Assessment
When to suspect it
Maintain a low threshold in any labouring woman with a risk factor — and remember that the textbook triad is unreliable; an abnormal CTG often comes first.
Symptoms and signs (classic teaching):
- Acute, severe, often "tearing" abdominal pain, which may break through a working epidural — sudden new pain in a previously comfortable woman on epidural is a red flag.
- Cessation or change in the pattern of contractions after a period of strong labour.
- Vaginal bleeding — but bleeding may be concealed intraperitoneally, so its absence is falsely reassuring.
- Fetal heart rate abnormalities — the most consistent sign. Recurrent variable or late decelerations progressing to a prolonged deceleration or bradycardia are typical; see ctg-interpretation. New fetal compromise in a VBAC labour is rupture until proven otherwise.
- Loss of station / recession of the presenting part — the head that was descending is suddenly higher on vaginal examination because it has slipped back through the rupture.
- Maternal tachycardia, hypotension and signs of shock disproportionate to visible blood loss — the hallmark of concealed haemorrhage; see shock-management.
- Scar tenderness, palpable fetal parts through the abdominal wall, or an altered abdominal contour.
- Haematuria if the bladder or lower segment is involved.
Figure J11.2 — Recognition dashboard for suspected uterine rupture, emphasising fetal bradycardia/CTG abnormality as the most consistent sign and the need to act before imaging.
Investigations — do not let them delay delivery
This is a clinical diagnosis confirmed at laparotomy. In an unstable woman or with a pathological CTG, delivery comes before any imaging.
- CTG / intermittent auscultation — your earliest and most sensitive monitor in a labouring woman, especially during VBAC.
- Bedside ultrasound (if immediately available and the woman is stable) may show free intraperitoneal fluid, an extra-uterine fetus, or absent fetal heart activity — but a normal scan never excludes rupture, and scanning must not delay theatre.
- Bloods: urgent FBC, cross-match (request the local massive-transfusion / emergency O-negative protocol), coagulation screen and fibrinogen, U&E. Send these as resuscitation begins, not before it.
- The diagnosis is frequently only confirmed when the abdomen is opened.
Management
EMERGENCY DRILL — suspected uterine rupture This is a "call everyone, open the abdomen now" emergency. Do not wait for confirmatory imaging.
- CALL FOR HELP — declare an obstetric emergency: most senior obstetrician, anaesthetist, theatre team, paediatrician/neonatal team, porters; activate the massive obstetric haemorrhage protocol and alert the blood bank.
- ABC + resuscitate — high-flow oxygen; two large-bore (14–16 G) IV cannulae; take cross-match/FBC/clotting as you cannulate; begin warmed crystalloid; lie the woman with left lateral tilt / manual uterine displacement.
- Activate massive transfusion — request emergency O-negative or group-specific blood early; transfuse to the local massive-haemorrhage ratio; give tranexamic acid 1 g IV (per WOMAN-trial practice for obstetric haemorrhage) and repeat per protocol.
- IMMEDIATE LAPAROTOMY — the only definitive treatment is to open the abdomen, deliver the fetus, stop the bleeding and repair or remove the uterus. Decision-to-delivery is measured in minutes — a sustained fetal bradycardia in this setting demands the fastest possible delivery.
- Resuscitate the neonate — anticipate a severely compromised, often asphyxiated baby; have the neonatal team and full resuscitation ready (see neonatal-resuscitation).
- Escalate / transfer level of care — if rupture is suspected at a district hospital without theatre, blood or a surgeon, this is a life-threatening referral: resuscitate, give TXA, communicate clinician-to-clinician and transfer by the fastest safe route — but never delay a laparotomy you are able to perform in order to transfer.
Surgical management
At laparotomy the priorities are: deliver the fetus, control haemorrhage, then decide between repair and hysterectomy.
- Deliver and assess. Lift out the fetus and placenta, evacuate clot, identify the rupture site (most often the lower segment / previous scar) and its extension. Inspect for lateral extension into the uterine vessels and broad ligament (risk of large vessel haemorrhage and ureteric injury) and for bladder involvement.
- Control bleeding. Clamp and oversew bleeding edges; bimanual compression while you organise. Stepwise devascularisation — uterine artery ligation, then if needed internal iliac (hypogastric) artery ligation — can buy time and control. Adjuncts for atonic or oozing components follow the same ladder as postpartum-haemorrhage (uterotonics, balloon, compression sutures), but rupture itself is a mechanical problem requiring surgical closure.
- Repair versus hysterectomy. Repair is appropriate when the tear is clean, accessible (typically a lower-segment scar rupture), the edges are healthy, the woman is stable and future fertility matters — and is recorded so that future pregnancies are managed as high-risk with planned repeat caesarean. Hysterectomy is indicated when bleeding is uncontrollable, the rupture is ragged/extensive, there is major lateral or cervical/vaginal extension, the tissue is friable, or the woman has completed her family — and the decision to proceed to hysterectomy must not be delayed once it is clear that repair will not secure haemostasis. A delayed, indecisive hysterectomy is a classic avoidable contributor to maternal death.
- Beware the ureter and bladder. Lateral extensions and bladder-flap involvement put the ureter at risk; identify it, and repair bladder injuries in layers with prolonged catheter drainage.
- Anaesthesia and ICU. General anaesthesia is usual for the unstable, bleeding patient. Anticipate dilutional and consumptive coagulopathy; correct with blood products guided by clotting/fibrinogen and, where available, viscoelastic testing. Plan for high-care or ICU recovery (see fluids-electrolytes-og for resuscitation principles).
Figure J11.3 — Emergency laparotomy and surgical decision pathway: parallel resuscitation and transfusion, delivery, haemorrhage control, repair-versus-hysterectomy criteria and bladder/ureter checks.
South African context
- The National Integrated Maternal and Perinatal Care Guideline (NDoH, 2024) is the national source of truth for intrapartum care, partogram use, oxytocin protocols and referral pathways; use it for level-specific practice.
- Prevention through good labour care is the highest-yield intervention: diligent partogram use to detect obstructed labour early, cautious and protocolised use of oxytocin (especially avoiding hyperstimulation), and great care with — or avoidance of — prostaglandins in a scarred uterus.
- Levels of care. District hospitals manage many labours without resident obstetricians or 24-hour theatre/blood access. VBAC and other high-risk parturients should ideally labour where caesarean and transfusion are immediately available; risk recognition and timely referral up the levels of care are core competencies. The Saving Mothers reviews repeatedly cite delayed recognition, delayed transfer and delayed surgery as avoidable factors.
- Tranexamic acid for obstetric haemorrhage and a defined massive obstetric haemorrhage protocol with emergency O-negative blood should be available and rehearsed at every delivering facility.
- HIV is highly prevalent in the SA obstetric population; anaemia is common and lowers haemorrhage reserve, reinforcing antenatal anaemia correction and a low threshold for early transfusion.
After the event
- Document fully — type and extent of rupture, what was done, blood loss, products given. This determines all future obstetric care.
- Counsel the woman and partner; offer debriefing and screen for psychological sequelae and birth trauma.
- Future pregnancies carry a markedly increased recurrence risk; the standard recommendation after a uterine rupture is planned repeat caesarean before labour in subsequent pregnancies, and labour is generally not offered. Discuss postpartum-contraception and inter-pregnancy spacing.
- Audit the case through the facility's perinatal/maternal morbidity-and-mortality meeting and report through the NCCEMD / Saving Mothers system where applicable.
Red flags / pitfalls
- Trusting the classic triad. Sudden pain + bleeding + cessation of contractions is the exception, not the rule. A new, unexplained fetal heart-rate abnormality (especially bradycardia) in a labouring woman with a scarred uterus is uterine rupture until proven otherwise — act, do not observe.
- Shock out of proportion to visible blood loss. Concealed intraperitoneal haemorrhage means the floor and pads can look dry while the woman is exsanguinating. Trust the maternal physiology (tachycardia, hypotension), not the visible loss.
- Imaging before delivery. Scanning or repeated examinations while a fetus is bradycardic and a mother is bleeding wastes the only resource that matters — time to theatre.
- Oxytocin and prostaglandins in the scarred uterus. Hyperstimulation precipitates rupture; prostaglandin induction in a previous caesarean is especially dangerous. Augment cautiously, protocol-driven, with close monitoring — and reassess promptly if labour is not progressing.
- Missing obstructed labour. A neglected obstructed labour — especially in a multipara — ruptures an unscarred uterus. The partogram alert/action lines and the appearance of a Bandl's ring are warnings to act, not to push harder. Never apply fundal pressure to overcome obstruction.
- Indecisive surgery. Persisting with repair of a ragged, bleeding rupture, or hesitating over hysterectomy in an unstable woman, costs lives. Control haemorrhage decisively.
- Forgetting the bladder and ureter in lower-segment and laterally extending tears.
- Confusing dehiscence with rupture when counselling — but equally, never dismiss scar tenderness or a CTG change as "just a dehiscence" in a labouring woman.
- Failing to plan the next pregnancy — discharge without clear documentation and a recurrence-risk conversation is a setup for a future catastrophe.
Evidence anchors
- National Integrated Maternal and Perinatal Care Guideline (NDoH, 2024), NDoH South Africa — national source of truth for intrapartum care, partogram, oxytocin use, levels of care and referral.
- Saving Mothers / NCCEMD (South Africa) — triennial confidential enquiry into maternal deaths; obstetric haemorrhage (including ruptured uterus) among the leading direct causes, with recurrent avoidable factors of delayed recognition, transfer and surgery.
- RCOG Green-top Guideline No. 45 — Birth After Previous Caesarean Birth (VBAC) — scar-rupture risk, candidate selection, induction/augmentation cautions and intrapartum monitoring.
- RCOG Green-top Guideline No. 52 — Prevention and Management of Postpartum Haemorrhage — massive-haemorrhage management principles, surgical haemostasis ladder and transfusion approach applicable to ruptured-uterus haemorrhage.
- WOMAN trial (Lancet 2017) — tranexamic acid 1 g IV early in obstetric haemorrhage reduces death from bleeding.
- NICE NG235 — Intrapartum care (2023) and NICE NG229 — Fetal monitoring in labour (2022) — intrapartum risk assessment and CTG categorisation, supporting early recognition of the fetal compromise that heralds rupture.
- WHO Labour Care Guide (2020) — structured intrapartum monitoring to detect obstructed/abnormal labour early.
(Standard teaching not separately line-itemed in the verified-source list — e.g. the ~0.5% VBAC rupture rate, classical-scar rupture being a few percent, Bandl's ring as a late sign, and the repair-versus-hysterectomy criteria — is presented cautiously and should be confirmed against the current guideline text before being quoted as exact figures.)