Sequential induction with prostaglandins and oxytocin has been reported to be associated with the highest OR for complete uterine ruptures in women either with or without a previous caesarean delivery. In women without caesarean delivery (CD) the adjusted OR was 48.0, whereas women with a previous CD had an OR of 16.1 [3].

Induction or augmentation of vaginal birth after caesarean section (VBAC), also called trial of labour after caesarean section (TOLAC), is associated with a two- to three-fold increased risk of uterine rupture and an approximately 1.5-fold increased risk of caesarean delivery compared with spontaneous onset of labour [4]. The use of higher oxytocin doses (>20 milliunits/minute) during VBAC augmentation increases the risk of uterine rupture by four-fold or greater [5].

Obstetric manoeuvres: Breech extraction had a high correlation with uterine rupture (AOR 42.6) [3]. Other obstetric manoeuvres include Internal podalic version and breech extraction for the delivery of the second twin, manual removal of the placenta, fetal surgery, shoulder dystocia and surgical termination of pregnancy. Unfortunately, some outdated obstetric procedures, such as ‘Kristeller’ manoeuvre (i.e. application of fundal pressure in second stage of labour) are still performed in some centres where competency in operative vaginal births is lacking, and this manoeuvre has been reported to be associated with uterine rupture.

High rotational forceps delivery [2]

Forceps delivery carried out in an unsuitable patient by an inexperienced obstetrician [2]

External cephalic version can be safely performed in women with a previous caesarean delivery scar. A systematic review of adverse outcomes of external cephalic version (ECV) and persisting breech presentation at term did not find any case of described uterine rupture after ECV [6].

Upper segment caesarean section scar has a higher (approximately 20-fold) risk of uterine rupture compared with lower segment scar [1].

Current scientific evidence appears to suggest that there is no significant difference in the rates of uterine rupture in VBAC with two or more previous caesarean births (92 per 10,000) compared with a single previous caesarean birth (68 per 10,000) [7].

An inter-pregnancy interval of less than 6 months between the previous caesarean section and subsequent VBAC was reported to be associated with an increased risk of uterine rupture (OR 2.66) and significant morbidity (AOR 1.95) [8].

A meta-analysis showed that single- and double-layer closure of a caesarean uterine incision are associated with similar incidence of uterine scar defects, as well as uterine dehiscence and uterine rupture in the subsequent pregnancy. The double-layer closure was associated with a significant increase in the residual myometrial thickness (RMT) on ultrasound compared with single-layer closure, which is of unclear clinical significance, as it was not associated with an increased incidence of uterine scar dehiscence or uterine rupture [9].

Risk of uterine rupture following myomectomy is significantly increased if the endometrial cavity has been opened during the procedure. Laparoscopic myomectomy, if performed by an expert, does not appear to carry any increased risk of subsequent uterine rupture compared with myomectomy via laparotomy.

Uterine perforation during intrauterine procedures could also lead to a uterine rupture during subsequent pregnancies.

Haemorrhage leading to hypovolaemic shock and need for blood transfusion

Bladder and ureteric injury

Peripartum hysterectomy and loss of future fertility

Maternal death – less common in a well-resourced setting; however, it can account for around 1%–15% of obstetric deaths in low-resource settings [2, 10].

Neonates born after uterine rupture were graded lower Apgar scores and had an increased risk of perinatal mortality compared with controls. [10]

Clinical negligence claims are especially likely in cases of uterine rupture following induction and augmentation of labour. To avoid this situation, one should promote informed consent and shared

decision-making in women undergoing VBAC. In addition, use of continuous electronic fetal heart rate monitoring using a cardiotocograph (CTG) should be recommended for timely diagnosis of uterine rupture.

As soon as possible, clear and accurate documentation of time of the uterine rupture, underlying predisposing factors, the decision to delivery interval (DDI), as well as a description of the rupture along with the type of surgery undertaken should be carried out. The whole sequence of events should be discussed with the patient by an experienced obstetrician or the obstetrician who performed the definitive surgery.