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Excessive molding can produce brain injuries and long-term sequelae. Understanding the loading of the fetal brain during the second stage of labor (fully dilated cervix, active pushing, and expulsion of fetus) could thus help predict the safety of the newborn during vaginal delivery. To this end, this study proposes a finite element model of the fetal head and maternal canal environment that is capable of predicting the stresses experienced by the fetal brain at the onset of the second phase of labor. Both fetal and maternal models were adapted from existing studies to represent the geometry of full-term pregnancy. Two fetal positions were compared: left-occiput-anterior and left-occiput-posterior. The results demonstrate that left-occiput-anterior position reduces the maternal tissue deformation, at the cost of higher stress in the fetal brain. In both cases, stress is concentrated underneath the sutures, though the location varies depending on the presentation. In summary, this study provides a patient-specific simulation platform for the study of vaginal delivery and its effect on both the fetal brain and maternal anatomy. Finally, it is suggested that such an approach has the potential to be used by obstetricians to support their decision-making processes through the simulation of various delivery scenarios.<\/jats:p>","DOI":"10.1115\/1.4065557","type":"journal-article","created":{"date-parts":[[2024,5,20]],"date-time":"2024-05-20T05:18:47Z","timestamp":1716182327000},"update-policy":"https:\/\/doi.org\/10.1115\/crossmarkpolicy-asme","source":"Crossref","is-referenced-by-count":6,"title":["Effects of Fetal Position on the Loading of the Fetal Brain During the Onset of the Second Stage of Labor"],"prefix":"10.1115","volume":"146","author":[{"given":"Alice M.","family":"Collier","sequence":"first","affiliation":[{"name":"Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erin","family":"Louwagie","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Columbia University, New York, NY 10027"},{"id":[{"id":"https:\/\/ror.org\/00hj8s172","id-type":"ROR","asserted-by":"publisher"}],"name":"Columbia University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6270-6445","authenticated-orcid":false,"given":"Ghaidaa A.","family":"Khalid","sequence":"additional","affiliation":[{"name":"School of Engineering, Cardiff University , Cardiff CF10 3AT, UK ; Baghdad 8998+QHJ, Iraq"},{"name":"Electrical Engineering Technical College, Middle Technical University, , Cardiff CF10 3AT, UK ; Baghdad 8998+QHJ, Iraq"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael D.","family":"Jones","sequence":"additional","affiliation":[{"name":"School of Engineering, Cardiff University, Cardiff CF10 3AT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristin","family":"Myers","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Columbia University, New York, NY 10027"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antoine","family":"Jerusalem","sequence":"additional","affiliation":[{"name":"Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"33","published-online":{"date-parts":[[2024,6,17]]},"reference":[{"key":"2024061716234165100_bib1","first-page":"1","article-title":"Best Practice in Labour and Delivery","volume-title":"Pelvic and Fetal Cranial Anatomy and Mechanism of Labour","year":"2009","edition":"1st ed."},{"issue":"1","key":"2024061716234165100_bib2","doi-asserted-by":"crossref","first-page":"46","DOI":"10.3109\/00016346009157836","article-title":"The Causes of Fetal Head Moulding in Labour","volume":"39","year":"1960","journal-title":"Acta. 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