Teaching Case

A 27-year-old woman (G4P3A1M3) had given birth to a 2.980 kg boy. She had no history of obstetrical or abdominal surgery. After the vaginal birth that was induced with uterotonica, the patient reported pain in the right iliac fossa. She remained haemodynamically stable and had no fever.

Ultrasound (US) two days postpartum shows an uterus with normal postpartum changes such as enlarged uterus volume and dilated para-uterine venous plexus. Hyper-reflective fatty tissue is seen in the right iliac fossa, pressure in this region is painful. There is no free intra-abdominal fluid. The appendix is not visualised.

A contrast-enhanced Computed Tomography (CT) examination of the abdomen is performed. This demonstrates a para-uterine structure on the right side that has an intermediate density (55HU). A complete rupture of the uterus wall cannot be delineated, although contours at the base are ill-defined. The right ureter is dilated above this structure.

Magnetic Resonance Imaging (MRI) three days postpartum shows a complete uterus rupture in the right posterolateral base. The T2-hypo-intense haemorrhagic content of the uterus lumen is spilled in the right iliac fossa through this defect. The haemorrhagic content expands into the right iliac fossa, explaining the pain in this region.

Uterus rupture is an important cause of postpartum haemorrhage because of its high morbidity and mortality rate [1]. It is an infrequent complication that usually occurs in a previously scarred uterus (mostly by caesarean section) [1, 2]. Complete uterus rupture of an unscarred uterus is very rare, with an incidence of only 0.006% in developed countries [3]. Risk factors for unscarred uterus rupture are multiparity, use of uterotonica during labour, macrosomia, uterus malformations and others [1, 2].

There are no highly specific signs of uterus rupture. Symptoms include vaginal haemorrhage and abdominal pain. If a significant amount of blood is lost, haemodynamic instability can occur [3].
Diagnostic procedures are urgent when uterus rupture is suspected. This ensures rapid therapeutic intervention, necessary to stop the bleeding and prevent or treat haemodynamic instability.

Ultrasound can easily demonstrate intra-abdominal free fluid in case of a rupture with massive haemorrhage. It is readily available in emergency setting and is also mastered by gynaecologists. Direct visualisation of an incomplete or small complete rupture in the uterus wall can be challenging [4].

Contrast-enhanced CT is the best examination to detect an active bleeding with arterial contrast blush [4]. It can often demonstrate the complete or incomplete defect in the wall of the uterus and allows a complete evaluation of the extent and location of the haemorrhagic contents.

MRI has the best contrast resolution between different tissue types. It can clearly show a defect in the uterus wall and provide detailed information about the characteristics of the tissues in proximity to this defect. However, MRI is not suited for a haemodynamically unstable patient or a patient that is moving due to pain. Most often an MRI is performed when US or CT is inconclusive or in case of contrast hypersensitivity [4].

In this case the patient remained haemodynamically stable and the clinicians opted for a conservative treatment. After a reassuring ultrasound 7 days later she went home. No follow-up CT or MRI was performed.

When the patient remains haemodynamically stable, a conservative approach can be justified. Resuscitation with fluids and packed cells is lifesaving in case of haemodynamic instability [1, 4]. When the uterus defect is small or incomplete it can be closed surgically, though most often a hysterectomy is required to prevent further complications such as bleeding or infection.