Evidence map›Paper›PMID 42489827›Full record

ArticleUltrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology2026

Levator hiatus area from 21 weeks' gestation to 8 years after first delivery according to vaginal parity: prospective cohort study with an 8-year recall extension.

F Siafarikas, J Šaltytė Benth, J Stær-Jensen, C Reimers, K Bø, M Ellström Engh

Abstract read
In one paragraph

Article in Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

F SiafarikasFaculty of Medicine, Division Akershus University Hospital, University of Oslo, Oslo, Norway.ORCID https://orcid.org/0000-0002-7413-8307
J Šaltytė BenthInstitute of Clinical Medicine, Campus Ahus, University of Oslo, Oslo, Norway.
J Stær-JensenDepartment of Obstetrics and Gynecology, Akershus University Hospital, Lørenskog, Norway.
C ReimersDepartment of Obstetrics and Gynecology, Oslo University Hospital, Oslo, Norway.
K BøDepartment of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway.ORCID https://orcid.org/0000-0003-1176-9272
M Ellström EnghFaculty of Medicine, Division Akershus University Hospital, University of Oslo, Oslo, Norway.

Funding

Helse Sør-Øst RHF 2799026Medisinske fakultet, Universitetet i Oslo
6 · The paper itself

Abstract

objectivesThe first aim was to describe longitudinal changes in levator hiatus area from 21 weeks' gestation in the first pregnancy to 1 and 8 years after first delivery, according to subsequent vaginal parity in women with vaginal delivery or Cesarean section (CS) at first delivery. The second aim was to assess the effect of subsequent vaginal delivery on levator hiatus area after first vaginal delivery.

methodsIn this prospective cohort study with an 8-year recall extension, 183 initially nulliparous women underwent three- and four-dimensional transperineal ultrasound examination at 21 weeks' gestation and 1 and 8 years after first delivery. The levator hiatus area at rest, during maximum pelvic floor muscle contraction and during maximum Valsalva maneuver was assessed at each timepoint. Participants with multiple vaginal deliveries (vaginal multiparae), only one vaginal delivery (vaginal primiparae), CS for all deliveries and vaginal birth after CS were compared. The differences between study groups in levator hiatus area over time were assessed using a linear mixed model.

resultsOverall, vaginal multiparae showed a statistically significant non-linear increase in levator hiatus area from 21 weeks' gestation to 8 years after first delivery (P < 0.001). In contrast, participants who delivered exclusively by CS showed a decrease in levator hiatus area from 21 weeks' gestation to the 8-year follow-up. Subsequent vaginal delivery after an initial vaginal delivery did not affect the levator hiatus area during Valsalva maneuver. At the 1-year and 8-year follow-up after the first vaginal delivery, levator hiatus area at rest remained unchanged in vaginal multiparae but decreased in vaginal primiparae. At the 8-year follow-up, vaginal multiparae had a larger hiatus area during pelvic floor muscle contraction than did vaginal primiparae.

conclusionsIn this study, the levator hiatus area was influenced by the mode of the first delivery and by subsequent vaginal deliveries. Overall, the levator hiatus area increased from 21 weeks' gestation to 8 years in participants with at least one vaginal delivery and decreased in those who delivered exclusively by CS. Subsequent vaginal delivery after a first did not seem to affect the levator hiatus area measured during Valsalva maneuver. © 2026 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Indexed as

Delivery, ObstetricParityPelvic FloorAdultCesarean SectionFemaleFollow-Up StudiesGestational AgeHumansLongitudinal StudiesMuscle ContractionPregnancyProspective StudiesUltrasonographyValsalva Maneuverdelivery modelevator ani musclepelvic floorpelvic organ prolapsevaginal delivery

Identifiers

PMID42489827
PMCPMC13432985

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.