King's College London

Case study of a woman who went into spontaneous preterm labour with a
trans-abdominal cerclage (TAC) in situ at 33 weeks’ gestation. In view of a risk
of uterine rupture, she was taken to theatre for examination under anesthesia ±
caesarean section. Under spinal analgesia the TAC sutures were palpable on VE,
having pulled through the now soft and shortened posterior wall of the cervix.
They were therefore cut and removed vaginally. She went on to have a vaginal
delivery of a healthy female infant. There are no published cases of women who
have had their TAC removed vaginally, allowing spontaneous vaginal delivery to
be achieved. In our experience it is not uncommon that the abdominal cerclage is found within the internal os at the time of scheduled caesarean section. This can occur even when the woman has been asymptomatic. This provides evidence that removal through the internal os is feasible and can prevent the need for caesarean delivery in rare cases. It also supports the need for careful ultrasound assessment prior to future conception, confirming the TAC is still in-tact.