{
  "abstract": "Background: The progesterone-to-metaphase II oocyte ratio (P/MII) combines trigger-day progesterone with mature oocyte count after retrieval. Its associations may reflect ovarian response and embryo allocation.\n\nMethods: This retrospective cohort included 7,778 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle records. Existing pregnancy analyses used 4,273 positive-transfer records. A linked clinical and laboratory source export enabled post hoc analyses using recorded extended culture counts, retrieval order, transfer dates, thawing records, and source-identifier grouping.\n\nResults: The original high-versus-low P/MII rate ratio for blastocysts per recorded 2PN zygote was 0.796 (95% CI 0.762–0.831). Among the same 5,821 culture-positive records, the adjusted rate ratio was 0.934 (0.902–0.968) with a 2PN denominator and 0.974 (0.945–1.005; P = 0.101) with the recorded culture denominator. The continuous culture-count association remained small (aRR 0.993 per 0.01, 0.989–0.997). The source recorded 6,148 first and 1,630 later retrievals. In 3,526 first-retrieval, date-consistent records without thawing evidence, the ratio term after inclusion of progesterone and MII was associated with clinical pregnancy flags (aOR 0.952, 0.919–0.986; P = 0.006) but was uncertain for live birth flags (0.968, 0.935–1.002; P = 0.067). Source-identifier-grouped live birth areas under the receiver operating characteristic curve (AUCs) were 0.623 with the components, 0.623 with P/MII, and 0.624 with all three.\n\nConclusions: Recorded associations depended on the culture population, denominator, and outcome. Incremental clinical usefulness was not established. These data do not support a physiological ratio mechanism or a clinical cutoff for trigger-day or freeze-all decisions.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Clinical Laboratory, Liuzhou Hospital, Guangzhou Women and Children’s Medical Center",
    "Department of Clinical Laboratory, Guigang Clinical Medical Research Center for Medical Laboratory, Guigang City People’s Hospital",
    "Liuzhou Municipal Liutie Central Hospital"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Yidong Wei"
    },
    {
      "affs": [
        1
      ],
      "name": "Yu Xu"
    },
    {
      "affs": [
        0
      ],
      "name": "Nuanfang Wei"
    },
    {
      "affs": [
        0
      ],
      "name": "Yu Chen"
    },
    {
      "affs": [
        0
      ],
      "name": "Yupei Zhang"
    },
    {
      "affs": [
        0
      ],
      "name": "Xueli Li"
    },
    {
      "affs": [
        2
      ],
      "name": "Haifan Wei"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5stxdf2sx01br.bib",
  "cited_by": 0,
  "doi": "10.3389/fendo.2026.1938120",
  "fulltext_url": "https://www.frontiersin.org/articles/10.3389/fendo.2026.1938120/full",
  "id": "5stxdf2sx01br",
  "issns": [
    "1664-2392"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fendo.2026.1938120/full",
  "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": [
    [
      "lcc",
      "RC648-665"
    ],
    [
      "openalex",
      "2739|Reproductive Biology and Fertility"
    ]
  ],
  "openalex": "W7224079078",
  "pdf_url": "https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2026.1938120/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-28",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/5stxdf2sx01br.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:20Z",
      "native_id": "10.3389/fendo.2026.1938120",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fendo.2026.1938120/full"
    },
    {
      "first_seen": "2026-10-31T14:22:05Z",
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      "url": "https://doi.org/10.3389/fendo.2026.1938120"
    }
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  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2739|Reproductive Biology and Fertility",
      "subfield": "epidemiology-public-health"
    }
  ],
  "title": "Trigger-day progesterone-to-mature-oocyte ratio, cycle-level blastocyst yield, and recorded embryo-transfer outcomes: a retrospective cohort study",
  "title_text": "Trigger-day progesterone-to-mature-oocyte ratio, cycle-level blastocyst yield, and recorded embryo-transfer outcomes: a retrospective cohort study",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T14:22:05Z",
  "url": "https://research.draconitic.com/paper/5stxdf2sx01br",
  "venue": "Frontiers in Endocrinology",
  "versions": []
}