This paper presents a case of a 36-year old female who experienced a rupture of her unscarred uterus during delivery of her child. She was induced with prostaglandins at 37 weeks for reduced fetal movements and her labor was augmented with oxytocin. A kiwi assisted vaginal delivery was performed in view of 2nd stage fetal bradycardia. A few hours post-delivery, she complained of chest pain. She was noted to be tachycardia and hypotensive. On examination, she had a tender abdomen with rebound and guarding. Investigations revealed that she had a 4g/dL drop in haemoglobin and a CT scan was suggestive of a uterine rupture. She underwent an exploratory laparotomy and was confirmed to have a posterior uterine wall rupture, which was repaired. She recovered well and was discharged on the 3rd post-operative day. Serious morbidity and mortality was likely avoided in view of a high index of suspicion. Induction and augmentation of labor have been known to predispose to uterine rupture. Fetal bradycardia may be the only sign of an intrapartum uterine rupture, hence the use of continuous electronic fetal monitoring is vital when these agents are being used.

It is well-known that uterine rupture is an obstetric catastrophe associated with previous scarring, with an incidence of 1 in 200 in those undergoing vaginal birth after caesarian delivery. Little is known though about its occurrence in an unscarred uterus.

Historically, risk factors for uterine rupture include obstetric trauma resulting from prolonged or neglected labour, fetal macrosomia, malpresentation, internal podalic version, breech extraction, manual cervical dilatation and instrumental deliveries.

In this age of modern obstetric practice, the previously recognized risk factors have become obsolete with the increased utilization of caesarian sections. Prolonged or neglected labours are rarely allowed with the introduction of the partogram. Fetal macrosomia and malpresentation would have been detected antenatally by the utilization of ultrasounds. Breech babies are now delivered by caesarian sections since the publication of the Term Breech Trial, and the rate of instrumental deliveries has decreased over the years due to a reduction in training hours, lack of senior supervision and fear of litigation.

Nevertheless, modern obstetrics also has its pitfalls. Induction and augmentation of labour play a big part in modern obstetric management and have been shown to predispose to uterine rupture. Other non-iatrogenic risk factors include advanced maternal age, multiparity, uterine anomalies and maternal connective tissue disease.

Though very rare, it has been estimated that the incidence of uterine rupture in an unscarred uterus ranges from 1 in 5700 to 1 in 20,000.

With Regards,
Sara Giselle
Associate Managing Editor
Journal of Critical Care Obsestrics & Gynocology