{
  "abstract": "Background: Biological sex may influence neonatal vulnerability to adverse perinatal outcomes, but sex-related differences in these outcomes remain underexplored. Male neonates may be more susceptible to perinatal asphyxia, metabolic acidosis, preterm birth, and morbidity, possibly due to sex-specific placental differences and inflammatory responses. Umbilical cord arterial pH (UApH) < 7.05 is used in Sweden to define neonatal acidemia, associated with poor outcomes. This study aimed to investigate the association between neonatal sex and adverse outcomes, focusing on UApH.\n\nMethods: This retrospective multicenter cohort study used data from the Swedish Perinatal Revision South Register (1995–2015). The cohort included live-born, singleton, vaginal births. Neonatal and maternal data were extracted, and logistic regression models compared outcomes between male and female neonates, adjusting for maternal age, gestational age, and birth weight.\n\nResults: Among 87 840 neonates, 51.6% were male. Male neonates had significantly higher adjusted odds of adverse outcomes compared with females: UApH < 7.05 (OR 1.18, 95% CI 1.07–1.30; P < 0.001), Apgar score < 7 at 5 min (OR 1.33, 95% CI 1.14–1.56; P < 0.001), CPAP use (OR 1.66, 95% CI 1.46–1.87; P < 0.001), NICU admission (OR 1.51, 95% CI 1.43–1.60; P < 0.001), hypoxic-ischemic encephalopathy (OR 2.24, 95% CI 1.29–3.90; P = 0.002) and central nervous system disease (OR 1.52, 95% CI 1.30–1.76; P < 0.001).\n\nConclusions: Male neonatal sex was associated with several adverse perinatal outcomes, including acidemia and neurological complications. These findings contribute to the understanding of sex-related differences in neonatal vulnerability and warrant further investigation.\n\nTrial registration: Not applicable.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Obstetrics and Gynaecology, Skåne University Hospital, Malmö, 205 01 Sweden",
    "Obstetrics and Gynaecology, Institution of Clinical Sciences Lund, Lund University, Lund, Sweden"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Wazhma Nassery Akel",
      "orcid": "0009-0007-4912-5962"
    },
    {
      "affs": [
        0
      ],
      "name": "Sara Abdulilah"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Mehreen Zaigham"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4a30zg13x3qb3.bib",
  "cited_by": 0,
  "doi": "10.1186/s12887-026-07865-5",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13711940/",
  "id": "4a30zg13x3qb3",
  "issns": [
    "1471-2431"
  ],
  "landing_url": "https://doi.org/10.1186/s12887-026-07865-5",
  "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",
      "Research"
    ],
    [
      "openalex",
      "2740|Neonatal Respiratory Health Research"
    ]
  ],
  "openalex": "W7224009096",
  "pdf_url": "https://link.springer.com/content/pdf/10.1186/s12887-026-07865-5.pdf",
  "pmcid": "PMC13711940",
  "pmid": "42947043",
  "published": "2026-10-27",
  "publisher": "BMC",
  "ris": "https://research.draconitic.com/paper/4a30zg13x3qb3.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T12:22:38Z",
      "native_id": "PMC13711940",
      "source": "pmc",
      "url": "https://doi.org/10.1186/s12887-026-07865-5"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2740|Neonatal Respiratory Health Research",
      "subfield": "general"
    }
  ],
  "title": "Sex-specific adverse neonatal outcomes and umbilical cord arterial ph at birth: a population-based cohort study",
  "title_text": "Sex-specific adverse neonatal outcomes and umbilical cord arterial ph at birth: a population-based cohort study",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T12:22:38Z",
  "url": "https://research.draconitic.com/paper/4a30zg13x3qb3",
  "venue": "BMC Pediatrics",
  "versions": []
}