{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T21:51:22Z","timestamp":1779918682391,"version":"3.53.1"},"reference-count":60,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,11,25]],"date-time":"2017-11-25T00:00:00Z","timestamp":1511568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"LabEx iMUST","award":["ANR-10-LABX-0064"],"award-info":[{"award-number":["ANR-10-LABX-0064"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Intrapartum fetal heart rate (FHR) monitoring constitutes a reference tool in clinical practice to assess the baby\u2019s health status and to detect fetal acidosis. It is usually analyzed by visual inspection grounded on FIGO criteria. Characterization of intrapartum fetal heart rate temporal dynamics remains a challenging task and continuously receives academic research efforts. Complexity measures, often implemented with tools referred to as approximate entropy (ApEn) or sample entropy (SampEn), have regularly been reported as significant features for intrapartum FHR analysis. We explore how information theory, and especially auto-mutual information (AMI), is connected to ApEn and SampEn and can be used to probe FHR dynamics. Applied to a large (1404 subjects) and documented database of FHR data, collected in a French academic hospital, it is shown that (i) auto-mutual information outperforms ApEn and SampEn for acidosis detection in the first stage of labor and continues to yield the best performance in the second stage; (ii) Shannon entropy increases as labor progresses and is always much larger in the second stage; (iii) babies suffering from fetal acidosis additionally show more structured temporal dynamics than healthy ones and that this progressive structuration can be used for early acidosis detection.<\/jats:p>","DOI":"10.3390\/e19120640","type":"journal-article","created":{"date-parts":[[2017,11,27]],"date-time":"2017-11-27T11:07:08Z","timestamp":1511780828000},"page":"640","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Information Theory to Probe Intrapartum Fetal Heart Rate Dynamics"],"prefix":"10.3390","volume":"19","author":[{"given":"Carlos","family":"Granero-Belinchon","sequence":"first","affiliation":[{"name":"Laboratoire de Physique, CNRS, Universit\u00e8 Claude Bernard Lyon 1, ENS de Lyon, Universit\u00e8 de Lyon, F-69342 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phane","family":"Roux","sequence":"additional","affiliation":[{"name":"Laboratoire de Physique, CNRS, Universit\u00e8 Claude Bernard Lyon 1, ENS de Lyon, Universit\u00e8 de Lyon, F-69342 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrice","family":"Abry","sequence":"additional","affiliation":[{"name":"Laboratoire de Physique, CNRS, Universit\u00e8 Claude Bernard Lyon 1, ENS de Lyon, Universit\u00e8 de Lyon, F-69342 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muriel","family":"Doret","sequence":"additional","affiliation":[{"name":"H\u00f4pital Femme M\u00e8re Enfant, Universit\u00e8 Lyon I, F-69677 Bron, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1094-7201","authenticated-orcid":false,"given":"Nicolas","family":"Garnier","sequence":"additional","affiliation":[{"name":"Laboratoire de Physique, CNRS, Universit\u00e8 Claude Bernard Lyon 1, ENS de Lyon, Universit\u00e8 de Lyon, F-69342 Lyon, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1016\/j.bpobgyn.2007.02.008","article-title":"Prevention of birth asphyxia: Responding appropriately to cardiotocograph (CTG) traces","volume":"21","author":"Chandraharan","year":"2007","journal-title":"Best Pract. 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