{
  "abstract": "Background: Urinary pregnanediol glucuronide (PdG) is a non-invasive marker of luteal progesterone exposure, but its interpretation depends on timing relative to ovulation. We evaluated whether urinary luteinizing hormone (LH)-derived reference points could approximate ultrasound-determined ovulation (USDO) for scheduling mid-luteal PdG assessment.\n\nMethods: This retrospective secondary analysis included 283 ultrasound-confirmed ovulatory cycles from 102 women. We evaluated the retrospectively identified urinary LH peak and the first urinary LH concentrations ≥10, ≥15, ≥20, ≥25, and ≥30 mIU/mL. PdG measured 6–9 days after each LH reference was compared with PdG measured on the corresponding USDO-timed day. A PdG threshold of ≥15 µg/mL was used for the primary descriptive classification, with sensitivity analyses at ≥5, ≥10, and ≥20 µg/mL. Ninety-five percent confidence intervals were estimated using participant-level cluster bootstrap.\n\nResults: First urinary LH ≥15 mIU/mL occurred a median of 0 days from USDO (IQR −0.5 to +1), with 70.0% and 80.7% of events occurring within ±1 and ±2 days, respectively. At PdG ≥15 µg/mL, overall agreement ranged from 74.3% to 82.2% across days +6 to +9, with AUC values of 0.764–0.835. Alternative PdG thresholds produced different trade-offs between positive and negative agreement, while ≥15 µg/mL provided a comparatively balanced descriptive profile.\n\nConclusions: First urinary LH ≥15 mIU/mL is a candidate prospective reference for scheduling day-specific mid-luteal urinary PdG assessment. The present study establishes a candidate timing strategy rather than a clinically actionable decision rule; a single LH-timed PdG result should not be used alone to diagnose luteal dysfunction or direct treatment. These findings are hypothesis-generating; numerical LH and PdG thresholds are assay-dependent, require prospective platform-specific validation, and should not be interpreted as diagnostic criteria for luteal phase deficiency unless validated in a clinical trial.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Family Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada",
    "Bruyère Health Research Institute, Ottawa, ON, Canada",
    "Hospices Civils de Lyon, Service de Biostatistique-Bioinformatique, Lyon, France",
    "Centre National de la Recherche Scientifique (CNRS), Laboratoire de Biométrie et Biologie Évolutive, Équipe Biostatistique-Santé, Villeurbanne, France",
    "Department of Family Practice, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Rene Leiva"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Rene Ecochard"
    },
    {
      "affs": [
        4
      ],
      "name": "Jonathan Yang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4gjmsedd2sb0x.bib",
  "cited_by": 0,
  "doi": "10.3389/fendo.2026.1992715",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13696250/",
  "id": "4gjmsedd2sb0x",
  "issns": [
    "1664-2392"
  ],
  "landing_url": "https://doi.org/10.3389/fendo.2026.1992715",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "2743|Ovarian function and disorders"
    ]
  ],
  "openalex": "W7221448376",
  "pdf_url": "https://europepmc.org/articles/PMC13696250?pdf=render",
  "pmcid": "PMC13696250",
  "pmid": "42935701",
  "published": "2026-10-12",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/4gjmsedd2sb0x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:38Z",
      "native_id": "PMC13696250",
      "source": "pmc",
      "url": "https://doi.org/10.3389/fendo.2026.1992715"
    },
    {
      "first_seen": "2026-10-30T12:20:20Z",
      "native_id": "10.3389/fendo.2026.1992715",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fendo.2026.1992715/full"
    },
    {
      "first_seen": "2026-10-30T12:22:24Z",
      "native_id": "MED:42935701",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42935701"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2743|Ovarian function and disorders",
      "subfield": "reproductive-child"
    }
  ],
  "title": "Timing luteal urinary pregnanediol glucuronide assessment using urinary luteinizing hormone: agreement with ultrasound-determined ovulation",
  "title_text": "Timing luteal urinary pregnanediol glucuronide assessment using urinary luteinizing hormone: agreement with ultrasound-determined ovulation",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:33:37Z",
  "url": "https://research.draconitic.com/paper/4gjmsedd2sb0x",
  "venue": "Frontiers in Endocrinology",
  "versions": []
}