{
  "abstract": "To compare the acute cardiovascular responses of non-pregnant and pregnant women to slow and deep breathing (SDB) at a range of breathing frequencies. Participants: Forty-one women (23 non-pregnant and 18 pregnant). Participants completed five different breathing conditions in a randomised order (5-min duration); spontaneous breathing (Sfr ), dynamic SDB breathing frequency (Dfr ), and three fixed breathing frequencies of 4 breaths. min-1 (4Ffr ), 6 breaths. min-1 (6Ffr ), and 8 breaths. min-1 (8Ffr ). Main Outcome Measures: Non-invasive beat-to-beat arterial blood pressure, heart rate and respired airflow were monitored continuously. The maximum amplitude of respiratory sinus arrhythmia (RSA) during SDB was 2.1 times higher than during spontaneous breathing (Sfr ) for both groups, maximising at 6 breaths. min-1 (0.25s ± 0.1 non-pregnant, 0.15s ± 0.1 pregnant). Although absolute RSA was significantly lower in pregnant women during spontaneous breathing (Sfr ; 0.07s vs. 0.12s non-pregnant), SDB increased RSA to the same level as non-pregnant women's spontaneous breathing levels. In both groups, the amplitude of blood pressure oscillations (both systolic and diastolic blood pressure) increased as breathing frequency declined, reaching a peak at 4 breaths. min-1 (4Ffr ), which was up to 4.5 times higher (14.3%, 10 mmHg) than during spontaneous breathing (Sfr ). Cardiovascular responses maximised at ≤6 breaths. min-1 and acute haemodynamic responses to SDB are similar in pregnant and non-pregnant women, despite absolute differences under spontaneous breathing conditions. If blood pressure oscillations underpin the anti-hypertensive effect of SDB, the data indicate that these can be amplified in pregnant women at frequencies between 4 and 6 breaths. min-1.",
  "abstract_shown": true,
  "affiliations": [
    "Centre for Midwifery & Women's Health, Bournemouth University, Bournemouth, United Kingdom.",
    "University Hospitals Dorset, NHS Foundation Trust, Bournemouth, United Kingdom."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Malika Felton"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Stephanie Grigsby"
    },
    {
      "affs": [
        0
      ],
      "name": "Vanora A Hundley"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/710edvewwg82h.bib",
  "cited_by": 0,
  "doi": "10.3389/fnetp.2026.1913383",
  "fulltext_url": "https://europepmc.org/articles/PMC13713283",
  "id": "710edvewwg82h",
  "issns": [
    "2674-0109"
  ],
  "landing_url": "https://europepmc.org/article/MED/42952596",
  "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": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "2705|Heart Rate Variability and Autonomic Control"
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  "openalex": "W3207548607",
  "pdf_url": "https://europepmc.org/articles/PMC13713283?pdf=render",
  "pmcid": "PMC13713283",
  "pmid": "42952596",
  "published": "2026-10-14",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/710edvewwg82h.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T00:20:41Z",
      "native_id": "MED:42952596",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42952596"
    },
    {
      "first_seen": "2026-10-31T12:23:51Z",
      "native_id": "PMC13713283",
      "source": "pmc",
      "url": "https://doi.org/10.3389/fnetp.2026.1913383"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2705|Heart Rate Variability and Autonomic Control",
      "subfield": "cardiovascular"
    }
  ],
  "title": "Acute cardiovascular responses to slow and deep breathing in normotensive non-pregnant and pregnant women.",
  "title_text": "Acute cardiovascular responses to slow and deep breathing in normotensive non-pregnant and pregnant women.",
  "type": "peer-reviewed",
  "updated_at": "2026-11-01T12:20:59Z",
  "url": "https://research.draconitic.com/paper/710edvewwg82h",
  "venue": "Frontiers in network physiology",
  "versions": []
}