Uterine Rupture

1. Clinical Overview

Summary

Uterine rupture is a catastrophic obstetric emergency involving a full-thickness disruption of the uterine wall, most commonly occurring at the site of a previous caesarean section scar during labour. It represents one of the most feared complications of trial of labour after caesarean (TOLAC), with the potential for rapid maternal and fetal deterioration. [1,2]

The condition occurs on a spectrum from incomplete rupture (scar dehiscence), where the uterine serosa remains intact, to complete rupture with full-thickness tearing and potential extrusion of the fetus and placenta into the peritoneal cavity. Prompt recognition and immediate surgical intervention are essential to prevent maternal death from haemorrhagic shock and fetal death from acute hypoxia. [3]

While the incidence is relatively low in modern obstetric practice in high-resource settings (approximately 0.5% of TOLAC attempts with lower segment scars), the consequences are devastating, requiring obstetric teams to maintain constant vigilance during labour in women with previous uterine surgery. [4]

Key Facts

Clinical Pearls

• CTG changes precede maternal symptoms: Fetal heart rate abnormalities (especially sudden-onset bradycardia) may be the ONLY warning sign before catastrophic collapse [5]
• "Baby floats up": Loss of station or ballottability of the presenting part on vaginal examination is pathognomonic—the fetus has extruded into the peritoneal cavity
• Contractions cease suddenly: After rupture, uterine contractility is lost—this sudden cessation should raise immediate suspicion
• Classical scar = contraindication to labour: Women with classical, T, or J-incision scars should undergo elective caesarean at 37-38 weeks due to 4-9% rupture risk [6]
• Concealed haemorrhage: Vaginal bleeding may be minimal or absent despite massive intraperitoneal bleeding
• Oxytocin is NOT contraindicated in TOLAC: However, prostaglandins carry a 2-3 fold increased rupture risk and should be avoided [7]
• Short inter-pregnancy interval: less than 18 months between caesarean and next conception increases rupture risk due to inadequate scar healing [8]
• Haemodynamic stability misleading: Maternal vital signs may remain deceptively stable initially due to physiological adaptation to pregnancy, delaying recognition

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2. Epidemiology

Incidence by Clinical Scenario

Geographic and Population Variation

Exam Detail: MRCOG Exam Focus: You should be able to quote the 0.5% rupture risk for TOLAC with one prior lower segment scar and the 4-9% risk with classical scars. Understand that prostaglandin induction approximately doubles the baseline risk, while oxytocin augmentation carries a modest but acceptable increase.

Risk Factors

Exam Detail: Short inter-pregnancy interval is an important modifiable risk factor. The RCOG recommends waiting at least 12-18 months after caesarean before conceiving again to allow adequate scar healing. [8]

Single-layer vs double-layer closure: This remains controversial. Some studies suggest single-layer closure may increase rupture risk, but others show no difference. The 2015 RCOG guideline does not mandate double-layer closure based on current evidence. [11]

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3. Pathophysiology

Scar Biomechanics

The pathophysiology of uterine rupture centres on the mechanical failure of scar tissue under the physiological stress of labour contractions. Following caesarean section, the myometrial incision heals through fibrosis and collagen deposition. However, scar tissue has only 30-50% of the tensile strength of normal myometrium and lacks the organized muscle architecture required for coordinated contraction. [12]

Collagen Remodelling Timeline:

Caesarean section
       ↓
Acute inflammatory phase (0-7 days)
       ↓
Proliferative phase (7 days - 6 weeks): Fibroblast infiltration, Type III collagen deposition
       ↓
Remodelling phase (6 weeks - 12-18 months): Type III → Type I collagen conversion
       ↓
Mature scar (12-18 months): Maximal tensile strength achieved (~50% of normal myometrium)

This explains why short inter-pregnancy intervals (less than 12-18 months) increase rupture risk—the scar has not yet matured to its maximal tensile strength. [8]

Mechanism of Rupture

Previous Caesarean Scar (area of biomechanical weakness)
               ↓
     Labour Onset / Induction
               ↓
     Uterine Contractions
     (especially augmented with oxytocin/prostaglandins)
               ↓
     Increasing Mechanical Stress on Scar
     (particularly lower segment during active labour)
               ↓
     Scar Thinning (less than 2-3 mm) → "Window" formation
               ↓
          ┌────────────────────────┐
          ↓                        ↓
    INCOMPLETE RUPTURE        COMPLETE RUPTURE
    (Scar dehiscence)        (Full-thickness tear)
          ↓                        ↓
    Serosa intact             Serosa breached
    Often asymptomatic        Peritoneal communication
          ↓                        ↓
    Incidental finding at     Fetal/placental extrusion
    repeat caesarean          into peritoneal cavity
                                   ↓
                     ┌─────────────┴─────────────┐
                     ↓                           ↓
            Fetal Compromise              Maternal Haemorrhage
            (cord compression,             (uterine arteries,
            placental separation)          broad ligament vessels)
                     ↓                           ↓
            Acute Fetal Hypoxia          Haemorrhagic Shock
            Fetal Bradycardia            Tachycardia, Hypotension
                     ↓                           ↓
            Neonatal HIE / Death         Maternal DIC / Death

Complete vs Incomplete Rupture

Anatomical Considerations

Lower Segment Scars:

• Account for > 95% of caesarean sections in modern practice
• Located in the thin, non-contractile lower uterine segment
• Subject to passive stretching rather than active contraction during labour
• Lower rupture risk (0.5%) due to reduced mechanical stress [4]

Classical Scars (Vertical Incision in Fundus/Upper Segment):

• Performed for: Extreme prematurity, transverse lie, lower segment myomas, placenta praevia with anterior placenta
• Located in the thick, highly contractile fundal myometrium
• Subject to maximal contractile forces during labour
• 4-9% rupture risk—labour is contraindicated [6]
• Can rupture before labour onset or in early pregnancy

T-Incisions, J-Incisions, Inverted T:

• Extension of lower segment incision into upper segment
• Combine mechanical disadvantage of both lower and upper segment scars
• Similar high rupture risk to classical scars (4-9%)

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4. Clinical Presentation

Warning Signs Hierarchy

The clinical presentation of uterine rupture varies from subtle fetal heart rate changes to catastrophic maternal cardiovascular collapse. Importantly, fetal signs of distress often precede maternal symptoms, making continuous fetal monitoring essential during TOLAC. [5]

Classic Triad (Present in less than 50% of Cases)

The "classic triad" is taught but is not reliably present in all cases:

1. Fetal distress (bradycardia on CTG)
2. Severe abdominal pain (continuous, localized to scar site or generalized)
3. Vaginal bleeding

CTG Features of Impending/Actual Rupture

Continuous CTG monitoring during TOLAC is mandatory because fetal heart rate changes are often the earliest detectable sign:

Clinical Pearl: Pearl: In many cases of uterine rupture, the first sign is a sudden, unexplained fetal bradycardia that does not respond to conservative measures (maternal repositioning, IV fluids, stopping oxytocin). If this occurs in a woman with a previous caesarean section, assume rupture until proven otherwise and proceed immediately to caesarean section. [5]

Maternal Symptoms

Maternal Signs on Examination

Exam Detail: MRCOG Viva Question: "What is the most common first sign of uterine rupture during TOLAC?"

Model Answer: "The most common first sign is fetal heart rate abnormalities, particularly the development of fetal bradycardia or a prolonged deceleration. CTG changes often precede maternal symptoms, which is why continuous electronic fetal monitoring is mandatory during TOLAC. Maternal symptoms such as abdominal pain and vaginal bleeding may follow, but relying on these alone risks delayed diagnosis and poor fetal outcome."

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5. Differential Diagnosis

Uterine rupture must be differentiated from other causes of acute fetal distress and maternal abdominal pain in labour. The key discriminators are the presence of a uterine scar (previous caesarean/myomectomy) and the pattern of symptoms (sudden onset, fetal bradycardia, loss of station).

Exam Detail: MRCOG Viva Question: "How would you differentiate between placental abruption and uterine rupture in a labouring woman with previous caesarean section?"

Model Answer:

Critical Point: Both require immediate delivery, so differentiation is less important than recognizing an acute obstetric emergency and acting promptly.

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6. Investigations

Clinical Diagnosis

Uterine rupture is a clinical diagnosis made on the basis of history (previous uterine scar), presentation (fetal distress, abdominal pain, haemorrhage), and examination (loss of station, maternal shock). There is no time for investigations in the acute setting—the priority is immediate laparotomy. [13]

Emergency Investigations (During Preparation for Theatre)

These investigations are performed simultaneously with preparation for emergency caesarean section, not as a prerequisite for surgery:

Pre-labour Risk Assessment (TOLAC Counselling)

In women considering TOLAC, certain investigations may inform risk stratification:

Exam Detail: RCOG Guidance on Scar Assessment:

The RCOG Green-top Guideline 45 (Birth After Previous Caesarean) does not recommend routine ultrasound assessment of lower segment thickness for predicting rupture risk during TOLAC. [6] While some studies suggest a correlation between thin scars (less than 2-3 mm) and increased rupture risk, the sensitivity and specificity are insufficient for clinical decision-making, and measurement is operator-dependent with poor reproducibility. [14]

Bottom Line: TOLAC suitability should be based on:

• Type of previous incision (review operative notes)
• Obstetric history (indication for previous CS, number of previous CS)
• Current pregnancy factors (estimated fetal weight, presentation, maternal choice)
• NOT on ultrasound scar thickness

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7. Management

Emergency Management Algorithm

SUSPECTED UTERINE RUPTURE
(Fetal bradycardia + previous CS + abdominal pain/bleeding)
          ↓
IMMEDIATE ACTIONS (Simultaneous):
  1. CALL FOR HELP
     • Obstetric Registrar/Consultant
     • Anaesthetic Registrar/Consultant
     • Senior Midwife (Coordinator)
     • Operating Theatre Team
     • Neonatal Team (Advanced Resuscitation)
     • Haematology (Massive Transfusion Protocol)
  
  2. STOP OXYTOCIN/PROSTAGLANDINS
  
  3. MATERNAL RESUSCITATION
     • High-flow oxygen (15 L/min via non-rebreather mask)
     • IV access: 2 × 14G/16G cannulae
     • IV fluid resuscitation: Crystalloid (Hartmann's/0.9% NaCl)
     • Blood samples: FBC, coagulation, crossmatch 4-6 units
  
  4. ACTIVATE MASSIVE TRANSFUSION PROTOCOL (if shocked)
          ↓
CATEGORY 1 CAESAREAN SECTION
(Decision to Delivery Interval less than 30 minutes)
          ↓
          ↓
INTRAOPERATIVE FINDINGS
          ↓
     ┌────────┴────────┐
     ↓                 ↓
INCOMPLETE        COMPLETE RUPTURE
RUPTURE           (Full-thickness tear)
(Dehiscence)            ↓
     ↓            Assess Rupture:
Repair at        • Location
time of CS       • Extent
                 • Degree of haemorrhage
                 • Involvement of bladder/bowel
                       ↓
                 ┌─────┴─────┐
                 ↓           ↓
           REPAIRABLE   NOT REPAIRABLE
           Small tear    Large/ragged tear
           Controlled    Uncontrollable bleeding
           bleeding      Lateral extension to vessels
                 ↓           ↓
           PRIMARY      HYSTERECTOMY
           REPAIR       (Subtotal vs Total)
           ± Drain            ↓
                        Consider:
                        • B-Lynch suture
                        • Internal iliac ligation
                        • IR embolization (if stable)

Resuscitation (ABCDE Approach)

Blood Product Replacement

Evidence Debate: Tranexamic Acid in Obstetric Haemorrhage: The WOMAN trial (2017) demonstrated that tranexamic acid (TXA) reduces death from bleeding by 31% when given within 3 hours of delivery in women with postpartum haemorrhage. [15] Although the trial focused on PPH, uterine rupture is a form of obstetric haemorrhage, and TXA should be administered early (1 g IV) as part of the massive transfusion protocol.

Surgical Options

Decision-Making at Laparotomy

Surgical Techniques

Primary Repair:

1. Deliver fetus and placenta
2. Debride non-viable/necrotic tissue at rupture edges
3. Achieve haemostasis (ligate bleeding vessels)
4. Close in layers:
   - First layer: Continuous 1-0 Vicryl (myometrium)
   - Second layer: Continuous 1-0 Vicryl (serosa)
5. Consider drain in peritoneal cavity (if contamination/haematoma)
6. Ensure bladder integrity if anterior (fill bladder with methylene blue/saline to check for leak)

Hysterectomy:

Clinical Pearl: Pearl: In cases of life-threatening haemorrhage, subtotal hysterectomy is faster and safer than total hysterectomy. The cervical stump is left in situ, avoiding dissection around the ureters and bladder base. This reduces operative time by 15-30 minutes in critically unwell patients. [16]

Adjunctive Haemostatic Measures

If bleeding persists despite repair/hysterectomy:

Neonatal Management

Exam Detail: MRCOG Viva Question: "At what gestation would you perform elective caesarean section in a woman with a previous classical caesarean scar, and why?"

Model Answer:

"I would recommend elective caesarean section at 37-38 weeks in a woman with a previous classical scar, due to the 4-9% risk of uterine rupture, which can occur before the onset of labour or in early labour. The classical incision is located in the thick, highly contractile upper segment of the uterus, which is subjected to significant mechanical stress even outside of active labour. There is evidence of rupture occurring as early as the late second trimester in some cases.

Delivery at 37-38 weeks balances the risk of prematurity-related complications (which are minimal at this gestation) against the risk of rupture. I would avoid prostaglandin cervical ripening entirely and ensure the patient understands that labour is absolutely contraindicated." [6]

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8. Complications

Maternal Complications

Fetal/Neonatal Complications

Exam Detail: Maternal Mortality: The maternal mortality from uterine rupture has declined dramatically over the past century due to improved access to emergency obstetric care. In high-resource settings, maternal mortality is approximately 0.5-1% for complete rupture, but in low-resource settings with limited access to emergency caesarean section and blood transfusion, mortality can exceed 5-10%. [3]

Perinatal Mortality: Similarly, perinatal mortality in high-resource settings is 5-10% for complete rupture, but in low-resource settings can exceed 30-50% due to delays in delivery. [3]

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9. Prognosis & Outcomes

Maternal Outcomes

Fetal Outcomes

Evidence Debate: Decision-to-Delivery Interval (DDI): The "30-minute rule" for Category 1 caesarean sections is a guideline, not an absolute threshold. While the RCOG recommends DDI less than 30 minutes for Category 1 emergencies, no specific DDI threshold guarantees good neonatal outcome. [18]

For uterine rupture specifically, studies suggest that DDI less than 18 minutes is associated with optimal outcomes, but achieving this in practice is extremely challenging. The key is to minimize delay through:

• Immediate recognition
• Efficient teamwork
• Pre-prepared emergency drills

Future Pregnancies

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10. Prevention & Counselling

Primary Prevention

TOLAC Counselling (Risk Stratification)

Women with one previous lower segment caesarean section should receive individualized counselling about TOLAC vs elective repeat caesarean section (ERCS):

TOLAC Success Rate: 72-76% in appropriately selected women [4]

TOLAC Eligibility Criteria (RCOG Green-top 45):

Absolute Contraindications to TOLAC:

• Previous classical, T, J, or inverted T incision
• Previous uterine rupture
• Previous transmural myomectomy
• Contraindication to vaginal delivery (e.g., placenta praevia, transverse lie)

Exam Detail: MRCOG Viva Question: "What would you counsel a woman about the risks and benefits of TOLAC vs elective repeat caesarean section (ERCS) if she has one previous lower segment caesarean section?"

Model Answer:

"I would provide balanced, evidence-based counselling covering the following:

TOLAC Success Rate: 72-76% chance of successful vaginal birth in appropriately selected women. [4]

Risks of TOLAC:

• Uterine rupture: 0.5% (1 in 200) [4]
• Emergency caesarean in labour: 20-25% (with associated increased maternal morbidity vs planned CS)
• Perinatal death or HIE: Very low absolute risk (~1-2 per 1000), but higher than ERCS

Benefits of TOLAC:

• Avoid major abdominal surgery
• Shorter recovery time (if successful)
• Lower risk of complications in future pregnancies (placenta praevia/accreta, repeat CS)
• Reduced risk of maternal morbidity (VTE, infection, adhesions) compared to multiple caesareans

Risks of ERCS:

• Surgical risks: Bleeding, infection, organ injury (bladder, bowel), VTE
• Longer recovery vs vaginal birth
• Increased risk of placenta praevia/accreta in future pregnancies
• Neonatal respiratory morbidity (TTN)

Factors Increasing TOLAC Success:

• Previous vaginal delivery (especially previous VBAC: 85-90% success)
• Spontaneous labour (vs induction)
• Non-recurrent indication for previous CS (e.g., breech)

Safety Measures for TOLAC:

• Delivery in hospital with immediate access to caesarean section and blood transfusion
• Continuous CTG monitoring throughout labour
• Immediate availability of obstetric and anaesthetic consultants
• Avoid prostaglandin induction (use oxytocin or mechanical methods if induction required)

I would also document the discussion, provide written information (RCOG patient information leaflet), and ensure shared decision-making respecting the woman's preferences."

Intrapartum Management of TOLAC

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11. Examination Focus (MRCOG)

High-Yield Viva Topics

Viva Question 1: TOLAC Risk Stratification

Question: "A 32-year-old woman attends your clinic at 36 weeks gestation. She had one previous lower segment caesarean section 18 months ago for breech presentation. She is keen for vaginal birth. How would you counsel her?"

Model Answer:

"I would adopt a structured, evidence-based approach to counselling:

1. Confirm Suitability for TOLAC:

• Review previous operative notes to confirm lower segment transverse incision (classical/T-incision = contraindication)
• Confirm adequate inter-pregnancy interval (≥18 months ✓)
• Check indication for previous CS (non-recurrent = favorable ✓)
• Assess current pregnancy factors: Presentation (cephalic?), estimated fetal weight (less than 4000 g?), maternal BMI

2. Discuss TOLAC Success Rate:

• Overall success rate: 72-76% [4]
• Her specific factors:
  • "Non-recurrent indication (breech): favorable"
  • "Adequate IPI: favorable"
  • If she has had a previous vaginal delivery, success rate increases to 85-90%

3. Discuss Risks of TOLAC:

• Uterine rupture: 0.5% (1 in 200) [4]
• Emergency caesarean in labour: 20-25%
• Very small increased risk of perinatal death/HIE compared to ERCS (absolute risk ~1-2 per 1000)

4. Discuss Risks of ERCS:

• Surgical risks (bleeding, infection, organ injury)
• Longer recovery
• Increased placenta praevia/accreta risk in future pregnancies

5. Safety Measures for TOLAC:

• Labour in hospital with immediate CS capability (Category 1 within 30 minutes)
• Continuous CTG monitoring
• Senior obstetric and anaesthetic cover immediately available
• If induction required: avoid prostaglandins (mechanical/oxytocin preferred)

6. Shared Decision-Making:

• Document discussion, provide RCOG patient information leaflet
• Respect her autonomy and preferences
• Arrange senior review if she has questions or concerns"

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Viva Question 2: Acute Management of Suspected Rupture

Question: "You are the registrar on labour ward. You are called to see a 34-year-old woman at 39 weeks gestation with one previous caesarean section. She is 6 cm dilated on oxytocin augmentation. The midwife reports a fetal bradycardia of 90 bpm for 8 minutes, and the woman is complaining of severe abdominal pain. What do you do?"

Model Answer:

"This is a Category 1 obstetric emergency—I am highly suspicious of uterine rupture given the combination of previous caesarean section, fetal bradycardia, and abdominal pain.

Immediate Actions (Simultaneous):

1. CALL FOR HELP:

• Obstetric consultant
• Anaesthetic consultant
• Senior midwife (coordinate)
• Operating theatre team (alert for Category 1 CS)
• Neonatal team (advanced resuscitation)

2. STOP OXYTOCIN INFUSION

3. ASSESS THE PATIENT (ABCDE):

• A/B: High-flow oxygen (15 L/min)
• C: Check pulse, BP, capillary refill; assess for signs of shock
• Perform vaginal examination: Assess cervical dilatation, check for loss of presenting part (pathognomonic for rupture)

4. RESUSCITATION:

• IV access: 2 × large-bore cannulae (14G/16G)
• Bloods: FBC, coagulation, crossmatch 4-6 units
• IV fluids: Crystalloid bolus (500-1000 mL Hartmann's)
• Activate massive transfusion protocol if shocked

5. PROCEED TO CATEGORY 1 CAESAREAN SECTION:

• Decision-to-delivery interval target: less than 30 minutes (ideally less than 18 minutes)
• Inform patient (if conscious and able to consent) that emergency delivery required
• General anaesthesia likely (faster than spinal if haemodynamically unstable)

Intraoperative Management:

• Deliver baby immediately
• Assess uterus for rupture (location, extent)
• If rupture confirmed:
  • Small tear, controlled bleeding → primary repair (double-layer closure)
  • Large tear, uncontrollable bleeding → hysterectomy (subtotal vs total)
• Administer tranexamic acid 1 g IV [15]
• Ensure neonatal team ready for resuscitation

Postoperative:

• HDU/ICU if massive transfusion or haemodynamic instability
• Debrief patient and family
• Document fully (including DDI)
• Incident report (Datix)
• Plan future pregnancies: elective CS at 37-38 weeks (TOLAC absolutely contraindicated)"

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Viva Question 3: Classical Scar Management

Question: "A 28-year-old woman books at 10 weeks gestation. She had a previous classical caesarean section at 26 weeks for severe preeclampsia with transverse lie. What are the implications for this pregnancy?"

Model Answer:

"A previous classical caesarean section is a high-risk scar with important implications:

1. Rupture Risk:

• 4-9% risk of uterine rupture [6] (compared to 0.5% for lower segment scar)
• Can rupture before labour onset or in early pregnancy (cases reported from late second trimester onwards)
• Labour is absolutely contraindicated

2. Management Plan:

Antenatal:

• High-risk antenatal clinic with consultant obstetrician
• Review previous operative notes (confirm classical incision)
• Serial growth scans (standard schedule)
• Consider serial assessment for symptoms of rupture (abdominal pain, bleeding, uterine tenderness)—though evidence for routine scar surveillance is lacking
• Plan delivery:
  • Elective caesarean section at 37-38 weeks (balance prematurity vs rupture risk)
  • "Rationale: Minimizes risk of spontaneous labour/rupture while avoiding significant prematurity"

Intrapartum:

• Elective caesarean under regional anaesthesia (unless contraindication)
• Senior obstetrician (consultant or senior registrar) to perform CS
• Warn of potential dense adhesions (previous preterm CS + classical incision)
• Be prepared for difficult delivery (upper segment incision required again; risk of bladder/bowel injury)

Postoperative:

• Standard postnatal care
• Contraception counselling: Recommend long-acting reversible contraception (LARC) to space pregnancies ≥18-24 months
• Counsel for future pregnancies: All future deliveries will be by elective CS at 37-38 weeks

3. Counsel Regarding Symptoms to Report:

• Severe abdominal pain
• Vaginal bleeding
• Uterine tenderness
• Feeling unwell
• Low threshold for emergency assessment if any concerns (risk of rupture before labour)"

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12. Patient / Layperson Explanation

What is uterine rupture?

Uterine rupture is a rare but very serious emergency where the wall of the womb (uterus) tears during pregnancy or labour. This most commonly happens at the site of a scar from a previous caesarean section. Think of it like a weak spot in a tire that can burst under pressure.

Who is at risk?

The main risk factor is having had a previous caesarean section. The scar from the caesarean is weaker than normal womb muscle, and during labour, the contractions can put stress on this scar, causing it to tear.

The risk depends on the type of scar:

• Lower segment scar (the standard caesarean most women have today): About 1 in 200 chance (0.5%) if you try for a vaginal birth
• Classical scar (a vertical cut up the middle of the womb, rarely done now): Much higher risk (4-9%, or about 1 in 15), so vaginal birth is not safe

Women without a previous caesarean very rarely experience uterine rupture (about 1 in 10,000 deliveries).

What are the warning signs?

If you are in labour with a previous caesarean scar, the medical team will monitor you closely for signs of rupture, including:

• Baby's heart rate dropping suddenly (this is often the first sign)
• Severe tummy pain that doesn't ease between contractions (normally pain should come and go)
• Heavy vaginal bleeding
• Feeling faint, unwell, or unusually anxious
• Change in the shape of your bump

What happens if uterine rupture occurs?

Uterine rupture is a medical emergency. The team will:

1. Call for help immediately—senior doctors, anaesthetists, and the neonatal (baby) team
2. Perform an emergency caesarean section to deliver the baby as quickly as possible (usually within 30 minutes)
3. Repair the tear in the womb during the operation

Sometimes, if the tear is very large or bleeding cannot be controlled, the doctors may need to remove the womb (hysterectomy) to save your life. This means you would not be able to have any more children, but the priority is keeping you safe.

What are the risks?

With prompt treatment, most mothers and babies are okay, but there are risks:

• For the mother: Heavy bleeding, needing a blood transfusion, needing a hysterectomy, or rarely, death (about 1 in 100 with complete rupture)
• For the baby: Lack of oxygen causing brain injury (hypoxic ischaemic encephalopathy), or rarely, stillbirth or death (about 5-10 in 100 with complete rupture)

Can I still have a vaginal birth after a caesarean?

Yes, many women can safely have a vaginal birth after caesarean (VBAC). About 7 in 10 women who try for a VBAC will succeed.

However, it's important to:

• Have a detailed discussion with your obstetrician about your individual risk
• Deliver in a hospital with immediate access to emergency surgery (not at home or in a midwife-led unit)
• Have continuous monitoring of the baby's heart rate during labour
• Avoid certain medications (like prostaglandins) that can increase the rupture risk

If you had a classical caesarean (a vertical scar), vaginal birth is not safe, and you will need a planned caesarean at around 37-38 weeks.

What about future pregnancies?

If you have had a uterine rupture:

• Future deliveries will always be by caesarean section—labour is not safe after a rupture
• You should wait at least 18-24 months before getting pregnant again to allow the scar to heal properly
• You will be cared for in a high-risk clinic during pregnancy

If you needed a hysterectomy, you will not be able to carry a pregnancy yourself, but you could explore options like surrogacy or adoption if you wish to have more children.

Where can I get more information?

• RCOG Patient Information: "Birth After Previous Caesarean Section" (available at www.rcog.org.uk)
• Your midwife or obstetrician can discuss your individual situation
• Birthrights (www.birthrights.org.uk): Information on rights and choices in childbirth

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13. References

1. Guise JM, et al. Systematic review of the incidence and consequences of uterine rupture in women with previous caesarean section. BMJ. 2004;329(7456):19-25. doi:10.1136/bmj.329.7456.19

2. Hofmeyr GJ, Say L, Gülmezoglu AM. WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture. BJOG. 2005;112(9):1221-1228. doi:10.1111/j.1471-0528.2005.00725.x

3. Al-Zirqi I, Stray-Pedersen B, Forsén L, Vangen S. Uterine rupture after previous caesarean section. BJOG. 2010;117(7):809-820. doi:10.1111/j.1471-0528.2010.02533.x

4. Landon MB, Hauth JC, Leveno KJ, et al. Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery. N Engl J Med. 2004;351(25):2581-2589. doi:10.1056/NEJMoa040405

5. Menihan CA, Kopas ML. Electronic fetal monitoring of uterine rupture. J Obstet Gynecol Neonatal Nurs. 2008;37(3):282-288. doi:10.1111/j.1552-6909.2008.00242.x

6. Royal College of Obstetricians and Gynaecologists. Birth After Previous Caesarean Birth. Green-top Guideline No. 45. London: RCOG; 2015.

7. Lydon-Rochelle M, Holt VL, Easterling TR, Martin DP. Risk of uterine rupture during labor among women with a prior cesarean delivery. N Engl J Med. 2001;345(1):3-8. doi:10.1056/NEJM200107053450101

8. Stamilio DM, DeFranco E, Pare E, et al. Short interpregnancy interval: risk of uterine rupture and complications of vaginal birth after cesarean delivery. Obstet Gynecol. 2007;110(5):1075-1082. doi:10.1097/01.AOG.0000286759.49895.46

9. Macones GA, Peipert J, Nelson DB, et al. Maternal complications with vaginal birth after cesarean delivery: a multicenter study. Am J Obstet Gynecol. 2005;193(5):1656-1662. doi:10.1016/j.ajog.2005.04.002

10. Cahill AG, Waterman BM, Stamilio DM, et al. Higher maximum doses of oxytocin are associated with an unacceptably high risk for uterine rupture in patients attempting vaginal birth after cesarean delivery. Am J Obstet Gynecol. 2008;199(1):32.e1-32.e5. doi:10.1016/j.ajog.2007.12.008

11. Roberge S, Demers S, Berghella V, et al. Impact of single- vs double-layer closure on adverse outcomes and uterine scar defect: a systematic review and metaanalysis. Am J Obstet Gynecol. 2014;211(5):453-460. doi:10.1016/j.ajog.2014.06.014

12. Jastrow N, Roberge S, Gauthier RJ, et al. Effect of birth weight on adverse obstetric outcomes in vaginal birth after cesarean delivery. Obstet Gynecol. 2010;115(2 Pt 1):338-343. doi:10.1097/AOG.0b013e3181c915da

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