Uterine rupture is uncommon but potentially fatal to both mother and baby. The incidence of uterine rupture is 0.05% of all pregnancies, occurring between 1 in 140 to 300 of women with a pre-existing scar. The risk increases with the number of caesarean sections; two previous sections carry a 3 to 5 fold risk over one previous section. The perinatal mortality is ten times that of the maternal mortality.
A spontaneous uterine rupture is very rare and most will occur in a woman with a pre-existing scar. The classical signs are unreliable and one should have a high index of suspicion. Sudden, tearing uterine pain, vaginal bleeding, decreased uterine contractions may be present. The mother may be hypotensive, tachycardiac and develop haematuria. The CTG is likely to show signs of foetal distress.
This is usually clinical, but an abdominal ultrasound may aid the diagnosis, time permitting.
Consider tocolytics, to stop contractions. Beware, many can exacerbate hypotension
Follow departmental guidelines for the Emergency treatment of massive obstetric haemorrhage.
[i] Entrez PubMed - Uterine rupture and scar dehiscence. A five year survey
[ii] Entrez PubMed - Uterine rupture
[iii] Perinatal review - Uterine rupture