{
  "abstract": "Objective\n\nThe aim of this study was to evaluate the relationship between intrapartum rectovaginal distance measured by transperineal ultrasonography and obstetric anal sphincter injury severity and second-stage labor duration in nulliparous women undergoing vaginal delivery.Methods\n\nThis prospective cohort study was conducted at a tertiary referral center in Istanbul, between September 2021 and January 2022. Of 200 consecutive nulliparous women with singleton pregnancies at ≥37 weeks' gestation, 148 who underwent vaginal delivery were included in the primary analysis. Intrapartum rectovaginal distance was measured in the midsagittal plane by 2D transperineal ultrasonography using a single operator during the inter-contraction rest period, at a fetal head station ranging from -1 to +1. Angle of progression and levator ani anteroposterior diameter were also recorded. Obstetric injury was graded per American College of Obstetricians and Gynecologists 2016 criteria; grade 3-4 laceration (severe obstetric anal sphincter injury) was the primary outcome.Results\n\nSevere obstetric anal sphincter injury occurred in 18 vaginal deliveries (12.2%). Rectovaginal distance was significantly shorter in women with severe obstetric anal sphincter injury (6.91±1.33 mm vs. 9.94±2.75 mm, p<0.001). Second-stage duration was longer with severe obstetric anal sphincter injury (125.8±6.5 vs. 91.3±18.0 min, p<0.001). Receiver operating characteristic analysis identified an rectovaginal distance cut-off of 8.1 mm (AUC=0.846; sensitivity 88.9%, specificity 80.8%). On multivariate logistic regression, rectovaginal distance (OR 0.516, 95%CI 0.373-0.713) and body mass index (OR 1.280, 95%CI 1.078-1.521) were independently associated with severe obstetric anal sphincter injury.Conclusion\n\nIntrapartum rectovaginal distance measurement by transperineal ultrasonography is a noninvasive, readily obtainable parameter that independently predicts severe obstetric anal sphincter injury and may support individualized intrapartum risk stratification. Multicenter validation with larger samples is warranted.",
  "abstract_shown": true,
  "affiliations": [
    "Sancaktepe Sehit Prof. Dr. Ilhan Varank Training and Research Hospital, Department of Gynecology and Obstetrics - Istanbul, Turkey.",
    "Sisli Hamidiye Etfal Training and Research Hospital, Department of Gynecology and Obstetrics - Istanbul, Turkey.",
    "Darıca Farabi Training and Research Hospital, Department of Gynecology and Obstetrics - Kocaeli, Turkey.",
    "Medicana Atakoy Hospital, Department of Gynecology and Obstetrics - Istanbul, Turkey."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Elif Görkem Bademci",
      "orcid": "0009-0005-1648-2176"
    },
    {
      "affs": [
        1
      ],
      "name": "Yağmur Şimşek Erdim",
      "orcid": "0000-0001-8124-6245"
    },
    {
      "affs": [
        2
      ],
      "name": "Ecem Yüksel Özsoy",
      "orcid": "0000-0002-7089-3639"
    },
    {
      "affs": [
        3
      ],
      "name": "Erkan Elçi",
      "orcid": "0000-0002-9792-6592"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fect0pa5w5h5j.bib",
  "cited_by": 0,
  "doi": "10.1590/1806-9282.20260531",
  "fulltext_url": "https://europepmc.org/articles/PMC13660572",
  "id": "fect0pa5w5h5j",
  "issns": [
    "0104-4230",
    "1806-9282"
  ],
  "landing_url": "https://europepmc.org/article/MED/42912052",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2745|Pelvic floor disorders treatments"
    ]
  ],
  "openalex": "W7221512629",
  "pdf_url": "https://europepmc.org/articles/PMC13660572?pdf=render",
  "pmcid": "PMC13660572",
  "pmid": "42912052",
  "published": "2026-10-12",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fect0pa5w5h5j.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:10Z",
      "native_id": "MED:42912052",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42912052"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2745|Pelvic floor disorders treatments",
      "subfield": "general"
    }
  ],
  "title": "Intrapartum rectovaginal distance as a predictor of obstetric anal sphincter injury: a prospective cohort study.",
  "title_text": "Intrapartum rectovaginal distance as a predictor of obstetric anal sphincter injury: a prospective cohort study.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:10Z",
  "url": "https://research.draconitic.com/paper/fect0pa5w5h5j",
  "venue": "Revista da Associacao Medica Brasileira (1992)",
  "versions": []
}