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Updated: Jun 3, 2026

Quantification of Levator Ani Hiatus Enlargement by Magnetic Resonance Imaging in Males and Females with Pelvic Organ Prolapse
Published on: April 17, 2019
Tridimensional sonographic anatomical changes on pelvic floor muscle according to the type of delivery
Jordi Cassadó Garriga1, Antoni Pessarrodona Isern, Montserrat Espuña Pons
1Department of Obstetrics and Gynaecology, Mútua Terrassa University Hospital, Plaça Doctor Robert 5, 08221 Terrassa, Spain. 29215jcg@comb.cat
Introduction And Hypothesis:
The aim of the study was to evaluate the association of avulsion and postnatal hiatal dimensions with delivery mode. These anatomical changes on pelvic floor muscle may be assessed by 3-4D ultrasonography.
Methods:
This is a prospective observational study that included 164 women: 20 nulliparous, 20 primigravid, and 124 postpartum women (62 at 1 month, 62 at 9 months postpartum). We performed an introital 3-4D ultrasonography to assess levator ani muscle's integrity, levator hiatal area at rest, on Valsalva, and on contraction.
Results:
Levator ani avulsion was diagnosed in 59.5% of forceps deliveries. There were no statistically significant differences in postnatal hiatal dimensions between normal vaginal deliveries at 9 months postpartum and nulligravid. Levator hiatal area was significantly higher after forceps delivery.
Conclusion:
Low incidence of levator avulsion takes place in normal vaginal deliveries. However, forceps delivery is the riskiest type of delivery for pelvic floor pathology and its recovery.
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