{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T23:21:14Z","timestamp":1787613674081,"version":"build-2736575974"},"reference-count":38,"publisher":"Georg Thieme Verlag KG","issue":"12","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Am J Perinatol"],"published-print":{"date-parts":[[2026,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>This study aimed to compare the fetal heart rate tracing (FHRT) and composite adverse outcomes among female versus male newborns delivered at term.<\/jats:p>\n                  <jats:p>The inclusion criteria of the retrospective study were non-anomalous singletons, delivered at \u226537 weeks after labor, whose sex assignment at birth was either female or male. The consecutive deliveries occurred over 15 months. Obstetricians\u2014blinded to maternal characteristics and outcomes\u2014interpreted the FHRT for the last 20 to 120\u2009minutes of labor. Composite neonatal and maternal adverse outcomes (CNAO and CMAO) were compared between the groups. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated.<\/jats:p>\n                  <jats:p>Of the 5,160 deliveries during the study period, 3,165 (61.3%) met the inclusion criteria, and among them, 1,514 (47.8%) were females, and 1,651 newborns (52.2%) were males. Obstetricians reviewed 358,620\u2009minutes of FHRT. Compared to females, the FHRT among males was significantly more likely to have severe late decelerations (aOR\u2009=\u20095.25; 95% CI: 1.16\u201323.83) or any severe decelerations (aOR\u2009=\u20091.21; 95% CI: 1.03\u20131.42). Whether the tracing was category I, II, or III, the incidence was similar. Cesarean delivery for non-reassuring FHRT was more common among male than female newborns (aOR\u2009=\u20091.21; 95% CI: 1.03\u20131.41). CNAO for male newborns was significantly higher than that for female newborns (aOR\u2009=\u20092.55; 95% CI: 1.35\u20134.84). Apgar score &lt;7 at 5\u2009minutes was the component of the CNAO that differed significantly (aOR\u2009=\u20093.16; 95% CI: 1.27\u20137.86). CMAO was also significantly higher for individuals who delivered male (9.3%) versus female (6.3%) newborns (aOR\u2009=\u20091.51, 95% CI: 1.16\u20131.98). Estimated blood loss \u22651,000\u2009mL was significantly more likely among male than female newborns (aOR\u2009=\u20091.51; 95% CI: 1.09\u20132.08).<\/jats:p>\n                  <jats:p>Among singleton pregnancies delivered at term, male fetuses, compared to females, are significantly more likely to have abnormalities of FHRTs and adverse outcomes.<\/jats:p>","DOI":"10.1055\/a-2807-4541","type":"journal-article","created":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T00:29:37Z","timestamp":1770856177000},"page":"1626-1634","source":"Crossref","is-referenced-by-count":0,"title":["Female versus Male Fetuses\u2014Variation in Fetal Heart Rate Tracing and Adverse Outcomes at Term"],"prefix":"10.1055","volume":"43","author":[{"given":"Aaron W.","family":"Roberts","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School at UTHealth Houston, Houston, Texas, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristen A.","family":"Cagino","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School at UTHealth Houston, Houston, Texas, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2158-4482","authenticated-orcid":false,"given":"Rachel L.","family":"Wiley","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Diego, San Diego, California, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4223-3203","authenticated-orcid":false,"given":"Fabrizio","family":"Zullo","sequence":"additional","affiliation":[{"name":"Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hector","family":"Mendez-Figueroa","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School at UTHealth Houston, Houston, Texas, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suneet P.","family":"Chauhan","sequence":"additional","affiliation":[{"name":"Department of Maternal-Fetal Medicine, Delaware Center for Maternal Fetal Medicine of ChristianaCare, Newark, Delaware, United States"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,2,19]]},"reference":[{"issue":"06","key":"ref1","doi-asserted-by":"crossref","first-page":"491.e1","DOI":"10.1016\/j.ajog.2011.04.024","article-title":"Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States","volume":"204","author":"H Y 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