Professional Reference articles are designed for health professionals to use. They are written by UK doctors and based on research evidence, UK and European Guidelines. You may find one of our health articles more useful.
Treatment of almost all medical conditions has been affected by the COVID-19 pandemic. NICE has issued rapid update guidelines in relation to many of these. This guidance is changing frequently. Please visit https://www.nice.org.uk/covid-19 to see if there is temporary guidance issued by NICE in relation to the management of this condition, which may vary from the information given below.
Most occur during labour; however, uterine scars following earlier caesarean may rupture during the third trimester before any contractions occur.
- Occult or incomplete rupture refers to a surgical scar separating but the visceral peritoneum staying intact. It is usually asymptomatic and does not require emergency surgery.
- Complete rupture can be:
Uterine rupture occurs extremely rarely - according to one study from the Netherlands, the incidence is between 0.7 and 5.1 per 10,000 deliveries in unscarred and scarred uteri, respectively. Following a previous caesarean section the incidence increases to 22-74/10,000 deliveries if vaginal birth after caesarean (VBAC) is attempted.
In a World Health Organization (WHO) systematic review of uterine rupture worldwide, the median incidence was 5.3 per 10,000 births. If only high‐income countries are taken into consideration, the mean incidence was around 3 per 10,000 deliveries.
- 87% of cases occur in women who have had a previous caesarean section:
- Classical vertical and T-shaped incisions carry a higher risk of later uterine rupture than the standard modern low transverse approach.
- An inter-delivery interval of less than 18-24 months increases the risk.
- The risk appears to be higher in pregnancies of gestational age greater than 40 weeks.
- Prior uterine surgery (including myomectomy, curettage, induced abortion, manual removal of the placenta). In 11.5% of cases there is no known uterine scar.
- Uterine anomalies - eg, undeveloped uterine horn.
- Trauma - eg, traffic collision.
- Use of rotational forceps.
- Obstructed labour.
- Induction of labour - prostaglandins should be used with caution during a trial of labour.
- Cervical laceration.
- Medically induced termination after 16 weeks of gestation.
- Placenta percreta or increta.
- Macrosomia and fetal anomaly - eg, hydrocephalus.
- Malpresentation (brow or face).
- Multiple pregnancy.
Other procedures with high risk of uterine rupture include internal podalic version and extraction, destructive operations and manoeuvres to relieve shoulder dystocia.
Management of uterine rupture depends on prompt detection and diagnosis. The classic signs (sudden tearing uterine pain, vaginal haemorrhage, cessation of uterine contractions, regression of the fetus) have been shown to be unreliable and frequently absent but any of the following should alert suspicion:
- Cardiotocograph (CTG) abnormalities, especially fetal bradycardia.
- Severe abdominal pain changing so that it persists between contractions.
- Chest or shoulder tip pain and sudden shortness of breath.
- Scar pain and tenderness.
- Abnormal vaginal bleeding or gross haematuria.
- Cessation of previously efficient uterine contractions.
- Maternal tachycardia, hypotension or shock.
- Movement away of the presenting part. Abdominal palpation may reveal obvious fetal parts as the fetus passes either partially or totally out of the uterus and into the abdominal cavity, with a high risk of intrapartum death.
If there is suspicion of uterine rupture, laparotomy may still be required even after a successful vaginal delivery, to assess damage and to control bleeding.
- Ultrasound can be used to diagnose rupture prior to labour when it may show an abnormal fetal position, haemoperitoneum or absent or thin uterine wall. Ultrasound is being analysed as a tool to predict uterine rupture. A French study suggests that a uterine wall thickness of greater than 4.5 mm has negative predictive value of 100% but unfortunately the positive predictive value of thickness less than 3.5 mm is poor at only 11.8%.
- Intrauterine pressure catheters are sometimes used but may fail to show loss of uterine tone or contractile patterns following uterine rupture.
- Resuscitation as necessary.
- Uterine repair if possible; hysterectomy may be indicated if haemorrhage persists - either total or sub-total, depending on the site of rupture and the patient's condition.
- There is no firm evidence regarding which type of thread, knotting or sequence of suturing is more favorable to reduce the risk of uterine rupture after VBAC or hysterotomy after myomectomy.
- In cases of lateral rupture involving lower uterine segment and uterine artery where haemorrhage and haematoma obscure the operative field, ligation of the ipsilateral hypogastric artery to stop bleeding may be needed.
- If a uterine repair has been achieved it is important to note that repeat rupture occurs in approximately 20% of cases.
In all cases of operative delivery, especially where there are risk factors for uterine rupture, a thorough examination of the uterus and birth canal is required.
- Postoperative infection.
- Damage to ureter.
- Amniotic fluid embolism.
- Massive maternal haemorrhage and disseminated intravascular coagulation (DIC).
- Pituitary failure.
- 6.2% of uterine ruptures are associated with perinatal (infant) death.
- 14-33% of women with uterine rupture require an emergency hysterectomy.
- In a Dutch nationwide study there were no pregnancy-related maternal deaths due to uterine rupture, but the perinatal (fetal) death occurred in 8.7%.
Unfortunately, uterine rupture cannot be adequately predicted for women wanting a trial of labour following a previous caesarean section. Doctors should review the medical history for risk factors and counsel regarding her relative risks, benefits, alternatives and probability of success. Women should be informed that planned VBAC is associated with an approximately 1 in 200 (0.5%) risk of uterine rupture.
Usually, shared care undertaken with an obstetrician is appropriate for any woman with a previous caesarean section.
A few circumstances (prior classic or T-shaped incision and unavailability of facilities for emergency caesarean delivery) will preclude a trial of labour. In most instances, however, National Institute for Health and Care Excellence (NICE) guidance advises that the decision about mode of birth following a previous caesarean should take into consideration:
- Maternal preferences and priorities.
- A general discussion of overall risks and benefits of repeat caesarean section versus VBAC, including the risk of an unplanned caesarean section.
- The risk of uterine rupture for all women with prior caesarean is 3 per 1,000. The risk with a trial of labour is 4.7/1,000 and if there is an elective repeat caesarean the rate is 0.26 per 1,000.
- Women who have had up to four caesarean deliveries should be advised that although the risk of uterine rupture is higher for trial of VBAC, it is still rare. The rate of uterine rupture is no higher in women who have had more than one caesarean than it is in women who have only had one, although the hysterectomy rate and need for transfusion are greater.
- 6% of uterine ruptures are associated with perinatal death. The risk of an intrapartum death is small in planned VBAC (10 per 10,000) but higher than those having a planned repeat caesarean (1 per 10,000). The effect of planned vaginal birth or repeat caesarean section on cerebral palsy is uncertain.
- Women who have had a previous caesarean section but also a vaginal birth can be advised that they are more likely to achieve a vaginal birth than women who have only had a caesarean birth.
Those who opt for a trial of labour should be offered continuous electronic fetal monitoring during delivery and care during labour in a unit where there is immediate access to emergency caesareans and an on-site blood transfusion service.
Induction of labour
- NICE guidance states that women with a previous caesarean section can be offered induction of labour but that they should be aware that the risk of uterine rupture is increased two- to three-fold, and the risk of needing an emergency caesarean is around 1.5-fold higher.
- When a planned VBAC is induced, the uterine rupture risk is higher if prostaglandin is used than in a non-prostaglandin-based regimen: in a Norwegian observational study of almost 19,000 women, the risk was 12.6 times higher after a prostaglandin induction than if the induction was mechanical or the labour spontaneous.
- When a planned VBAC is augmented, the oxytocin dose should be titrated such that contraction frequency is no more than 4 in 10 minutes. Research supports a maximum oxytocin dose of 20 mU/minute in trials of labour, to avoid an unacceptably high (4 x greater) risk of uterine rupture.
- Decisions regarding induction and augmentation of a planned VBAC should be made by the woman and a consultant obstetrician.
Further reading and references
Kieser KE, Baskett TF; A 10-year population-based study of uterine rupture. Obstet Gynecol. 2002 Oct100(4):749-53.
Zwart JJ, Richters JM, Ory F, et al; Uterine rupture in The Netherlands: a nationwide population-based cohort study. BJOG. 2009 Jul116(8):1069-78
Hofmeyr GJ, Say L, Gulmezoglu AM; WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture. BJOG. 2005 Sep112(9):1221-8. doi: 10.1111/j.1471-0528.2005.00725.x.
Halassy SD, Eastwood J, Prezzato J; Uterine rupture in a gravid, unscarred uterus: A case report. Case Rep Womens Health. 2019 Oct 1724:e00154. doi: 10.1016/j.crwh.2019.e00154. eCollection 2019 Oct.
Guise JM, Eden K, Emeis C, et al; Vaginal birth after cesarean: new insights. Evid Rep Technol Assess (Full Rep). 2010 Mar(191):1-397.
Tanos V, Toney ZA; Uterine scar rupture - Prediction, prevention, diagnosis, and management. Best Pract Res Clin Obstet Gynaecol. 2019 Aug59:115-131. doi: 10.1016/j.bpobgyn.2019.01.009. Epub 2019 Feb 10.
Grobman WA, Lai Y, Landon MB, et al; Prediction of uterine rupture associated with attempted vaginal birth after cesarean delivery. Am J Obstet Gynecol. 2008 Apr 23.
Birth after previous caesarean section; Royal College of Obstetricians and Gynaecologists (Oct 2015)
Caesarean section; NICE Clinical Guideline (November 2011 - last updated September 2019)
Landon MB, Spong CY, Thom E, et al; Risk of uterine rupture with a trial of labor in women with multiple and single prior cesarean delivery. Obstet Gynecol. 2006 Jul108(1):12-20.
Intrapartum care for healthy women and babies; NICE Guideline (Dec 2014, updated Feb 2017)
Induction of labour; NICE Clinical Guideline (July 2008 - currently under review)
Al-Zirqi I, Stray-Pedersen B, Forsen L, et al; Uterine rupture after previous caesarean section. BJOG. 2010 Jun117(7):809-20. doi: 10.1111/j.1471-0528.2010.02533.x. Epub 2010 Mar 24.
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 May 1.