{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T16:39:05Z","timestamp":1782319145928,"version":"3.54.5"},"reference-count":31,"publisher":"Georg Thieme Verlag KG","issue":"S 01","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Am J Perinatol"],"published-print":{"date-parts":[[2024,5]]},"abstract":"<jats:p>\n            Objective\u2003Internal contraction monitoring provides a quantitative assessment of intrauterine resting tone. During the course of labor, elevated intrauterine resting tone may be identified. We hypothesized that elevated intrauterine resting tone could lead to compression of the spiral arteries, thus limiting uterine blood flow and resulting in neonatal compromise. Therefore, our objective was to assess the association between elevated resting tone during labor and neonatal morbidity.<\/jats:p><jats:p>\n            Study Design\u2003This was a secondary analysis of a prospective cohort study of singleton deliveries at \u226537 weeks of gestation. Patients with ruptured membranes and an intrauterine pressure catheter in place for at least 30\u2009minutes prior to delivery were included. Intrauterine resting tone was calculated as the average baseline pressure between contractions during the 30\u2009minutes prior to delivery. The study group had elevated intrauterine resting tone, defined as intrauterine resting tone \u226575th percentile (\u226512.3\u2009mm Hg). Primary outcome was composite neonatal morbidity: hypoxic\u2013ischemic encephalopathy, hypothermia treatment, intubation, seizures, umbilical arterial pH \u22647.1, oxygen requirement, or death. Secondary outcomes included umbilical artery pH &lt;7.2, lactate \u22654 mmol\/L, and rates of neonatal intensive care unit admission.<\/jats:p><jats:p>\n            Results\u2003Of the 8,580 patients in the cohort, 2,210 (25.8%) met the inclusion criteria. The median intrauterine resting tone was 9.7\u2009mm Hg (interquartile range: 7.3\u201312.3\u2009mm Hg). Elevated resting tone was associated with a shorter median duration of the first stage of labor (10.0 vs. 11.0\u2009hours, p\u2009&lt;\u20090.01) and lower rates of labor induction and oxytocin augmentation (p\u2009&lt;\u20090.01). Neonatal composite morbidity was higher among patients with elevated intrauterine resting tone (5.1 vs. 2.9%, p\u2009=\u20090.01). After adjusting for chorioamnionitis and amnioinfusion, elevated intrauterine resting tone was associated with increased risk of neonatal morbidity (adjusted odds ratio: 1.70, 95% confidence interval: 1.06\u20132.74).<\/jats:p><jats:p>\n            Conclusion\u2003Our findings suggest that elevated intrauterine resting tone is associated with increased risk of neonatal composite morbidity.<\/jats:p><jats:p>\n            Key Points\n          <\/jats:p>","DOI":"10.1055\/a-2022-9588","type":"journal-article","created":{"date-parts":[[2023,1,31]],"date-time":"2023-01-31T23:55:46Z","timestamp":1675209346000},"page":"e1344-e1351","source":"Crossref","is-referenced-by-count":2,"special_numbering":"S","title":["Association between Elevated Intrauterine Resting Tone during Labor and Neonatal Morbidity"],"prefix":"10.1055","volume":"41","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9375-5047","authenticated-orcid":false,"given":"Rebecca R.","family":"Rimsza","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, Washington University in Saint Louis, St. Louis, Missouri"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nandini","family":"Raghuraman","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, Washington University in Saint Louis, St. Louis, Missouri"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ebony B.","family":"Carter","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, Washington University in Saint Louis, St. Louis, Missouri"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeannie C.","family":"Kelly","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, Washington University in Saint Louis, St. Louis, Missouri"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alison G.","family":"Cahill","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Dell School of Medicine, University of Texas at Austin, Austin, Texas"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6491-6910","authenticated-orcid":false,"given":"Antonina I.","family":"Frolova","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, Washington University in Saint Louis, St. Louis, Missouri"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2023,2,24]]},"reference":[{"issue":"01","key":"ref1","first-page":"18","article-title":"A quantitative study of the 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