Evidence map›Paper›PMID 42157565›Full record

ArticleActa obstetricia et gynecologica Scandinavica2026

Association between maternal and fetal characteristics and levator hiatal dimensions in the second stage of labor.

Mariya Kovalenko, Giulia Zamagni, Claudia Montero Carreras, Sana Usman, Arwa Hanidu, Tamara Stampalija, Lorenzo Monasta, Christoph Lees

Abstract read
In one paragraph

Article in Acta obstetricia et gynecologica Scandinavica, 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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2 · The registry

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3 · Its place in the literature

Who cites it

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No citing paper in PubMed yet.

4 · The record

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5 · Who and what money

Authors and funding

8 authors.

Mariya KovalenkoDepartment of Digestion, Metabolism and Reproduction, Imperial College London, London, UK.ORCID https://orcid.org/0000-0001-9672-0237
Giulia ZamagniClinical Epidemiology and Public Health Research Unit, Institute for Maternal and Child Health-IRCCS "Burlo Garofolo", Trieste, Italy.
Claudia Montero CarrerasCentre for Fetal Care, Queen Charlotte's and Chelsea Hospital, Imperial College, Healthcare NHS Trust, London, UK.ORCID https://orcid.org/0009-0007-5603-2887
Sana UsmanDepartment of Digestion, Metabolism and Reproduction, Imperial College London, London, UK.
Arwa HaniduDepartment of Digestion, Metabolism and Reproduction, Imperial College London, London, UK.
Tamara StampalijaUnit of Fetal Medicine and Prenatal Diagnosis, Institute for Maternal and Child Health IRCCS "Burlo Garofolo", Trieste, Italy.
Lorenzo MonastaClinical Epidemiology and Public Health Research Unit, Institute for Maternal and Child Health-IRCCS "Burlo Garofolo", Trieste, Italy.
Christoph LeesDepartment of Digestion, Metabolism and Reproduction, Imperial College London, London, UK.ORCID https://orcid.org/0000-0002-2104-5561

Funding

National Institute for Health Research (NIHR) Biomedical Research Centre based at Imperial College Healthcare NHS Trust and Imperial College LondonPrincess Nourah bint Abdulrahman University and Saudi Embassy P90027
6 · The paper itself

Abstract

introductionLittle is known about the pelvic floor hiatal dimensions in labor, despite this being the soft tissue complex through which the fetus passes in a vaginal delivery. Intrapartum assessment of pelvic floor hiatal dimensions, particularly in the second stage of labor, may improve understanding of the variation in levator hiatal measurements and their change between maternal and fetal characteristics. STUDY

designTo assess the levator hiatal dimensions at rest during the passive second stage of labor using three-dimensional (3D) transperineal ultrasound, participants were consented prospectively, and ultrasound assessment was performed. The study population comprised nulliparous women at term (37-42 gestation) with a live singleton pregnancy. MATERIAL AND

methodsParticipants eligible for participation were recruited for the "SONO-BIRTH" study. Transperineal ultrasound was performed in the second stage of labor. The 3D pelvic floor volumes were uploaded into software to measure the levator hiatal area, levator hiatal circumference, transverse hiatal diameter, and the anteroposterior hiatal distance. Maternal characteristics (age, body mass index, and ethnicity) were collected from antenatal booking forms. Other variables including gestational age and head-perineum distance (HPD) were recorded at the time of the ultrasound assessment, as well as birthweight.

resultsOf 186 participants consecutively recruited, 153 ultrasound volumes were measured. For the maternal characteristic of age, a significant association was observed with increasing maternal age and levator hiatal area (LHa) (β = 0.26 cm

conclusionsWe report the relationship between the levator muscle pelvic floor dimensions in the passive second stage of labor and maternal age, BMI, ethnicity, and gestational age. A higher fetal head station is associated with smaller pelvic floor dimensions as is non European ethnicity.

Indexed as

Labor Stage, SecondPelvic FloorAdultFemaleGestational AgeHumansImaging, Three-DimensionalPregnancyProspective StudiesUltrasonography, Prenatalimaginginterobserver variabilityintrapartumlevator ani muscle

Identifiers

PMID42157565
PMCPMC13308973

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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.