Levator trauma in labor: a challenge for obstetricians, surgeons and sonologists

Levator trauma in labor: a challenge for obstetricians, surgeons and sonologistsRecent advances in pelvic floor assessment have led to the rediscovery of a form of maternal birth trauma that was first described in 1907 1 but is absent from modern textbooks.Avulsion of the pubovisceral muscle from the pelvic sidewall seems to occur in 15-30% of vaginally parous women.Its prevalence is probably on the rise, as the likelihood of trauma seems to increase with higher maternal age at first delivery.Levator avulsion appears to be a significant part of the missing link between vaginal childbirth and prolapse and is likely to be the root cause of many cases of recurrence after prolapse surgery.At present, no techniques exist for the surgical repair of resulting defects.However, it is fortuitous that, hot on the heels of the rediscovery of levator avulsion and its significance, we seem to have chanced upon a means of dealing with anterior compartment prolapse in the presence of such trauma.Transobturator fixation of anterior compartment mesh, featured in this issue by Ralf Tunn of Berlin 2 , appears to cross the hiatus at the site of the defect and to provide support precisely where it is most needed.As shown by Dr Tunn, the meshes used for transobturator repair are identified easily by ultrasound, and imaging has already provided some surprising insights into the nature and mechanism of action of this new surgical technique.Over the last three decades, we have learned a lot about the epidemiological link between vaginal childbirth and pelvic floor dysfunction.Vaginal delivery is associated with a relative risk of 2-3 for fecal incontinence 3 , and we think we know how to explain this.Trauma to the pudendal nerve was investigated extensively in the 1980s and 90s 4,5 .Obstetric tears of the external and internal anal sphincters are familiar to every resident in obstetrics and gynecology after their first few weeks in training, and there is a lot of ongoing work to optimize detection and postpartum repair 6,7 .As regards stress urinary incontinence, the relative risk is about the same 3 , despite the fact that we do not really know which structures are responsible.The epidemiological link between childbirth and pelvic organ prolapse is stronger and particularly well established, with a relative risk of between 4 and 10 8 .Despite all these research data, there really are no prospects yet for preventative intervention.Elective Cesarean section, the one potentially prophylactic intervention, may well be associated with so much shortand longterm morbidity and costs to the taxpayer as to defeat the purpose.This is an unfortunate state of affairs, as demographic change in virtually all societies, especially delayed childbearing and increasing obesity, may well be leading