Evaluating fetal head dimension changes during labor using open magnetic resonance imaging
-
Christian Bamberg
,
Jan Deprest
Abstract
Aim:
Fetal skull molding is important for the adaptation of the head to the birth canal during vaginal delivery. Importantly, the fetal head must rotate around the maternal symphysis pubis. The goals of this analysis were to observe a human birth in real-time using an open magnetic resonance imaging (MRI) scanner and describe the fetal head configuration during expulsion.
Methods:
Real-time cinematic MRI series (TSE single-shot sequence, TR 1600 ms, TE 150 ms) were acquired from the midsagittal plane of the maternal pelvis during the active second stage of labor at 37 weeks of gestation. Frame-by-frame analyses were performed to measure the frontooccipital diameter (FOD) and distance from the vertex to the base of the fetal skull.
Results:
During vaginal delivery in an occiput anterior position, the initial FOD was 10.3 cm. When expulsion began, the fetal skull was deformed and elongated, with the FOD increasing to 10.8 cm and 11.2 cm at crowning. In contrast, the distance from the vertex to the base of the skull was reduced from 6.4 cm to 5.6 cm at expulsion.
Conclusions:
Fetal head molding is the change in the fetal head due to the forces of labor. The biomechanics of this process are poorly understood. Our visualization of the normal mechanism of late second-stage labor shows that MRI technology can for the first time help define the changes in the diameters of the fetal head during active labor.
Funding: The project was supported by a public grant (TSB Technologiestiftung Berlin-Zukunftsfonds Berlin). The funding source had no role in the collection, analysis, or interpretation of the data, writing support, and the decision to submit the article for publication.
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The authors stated that there are no conflicts of interest regarding the publication of this article.
©2017 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Editorial
- Intrapartum care
- Recommendation and Guidelines for Perinatal Practice
- Delivery modes in case of fetal malformations
- Review article
- Obstetric analgesia – update 2016
- Highlight articles
- Risk factors and outcomes in “well-selected” vaginal breech deliveries: a retrospective observational study
- Induction of labor in breech presentation at term: a retrospective cohort study
- Evaluating fetal head dimension changes during labor using open magnetic resonance imaging
- Risk factors of uterine rupture with a special interest to uterine fundal pressure
- Diagnostic accuracy of fetal scalp lactate for intrapartum acidosis compared with scalp pH
- Reference values for Lactate Pro 2™ in fetal blood sampling during labor: a cross-sectional study
- Linear and non-linear analysis of uterine contraction signals obtained with tocodynamometry in prediction of operative vaginal delivery
- Evaluation of simparteam – a needs-orientated team training format for obstetrics and neonatology
- Transient fetal blood redistribution associated with maternal supine position
- Original articles
- Underlying causes of neonatal deaths in term singleton pregnancies: home births versus hospital births in the United States
- Fourfold increase in prevalence of gestational diabetes mellitus after adoption of the new International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria
- Hematological changes in severe early onset growth-restricted fetuses with absent and reversed end-diastolic flow in the umbilical artery
- Breast milk feeding in infants with inherited metabolic disorders other than phenylketonuria – a 10-year single-center experience
- Clinical significance of a false positive glucose challenge test in patients with a high body mass index
- Obituary
- Obituary – Edward Ogata (1945–2017)
- Congress Calendar
- Congress Calendar
Artikel in diesem Heft
- Frontmatter
- Editorial
- Intrapartum care
- Recommendation and Guidelines for Perinatal Practice
- Delivery modes in case of fetal malformations
- Review article
- Obstetric analgesia – update 2016
- Highlight articles
- Risk factors and outcomes in “well-selected” vaginal breech deliveries: a retrospective observational study
- Induction of labor in breech presentation at term: a retrospective cohort study
- Evaluating fetal head dimension changes during labor using open magnetic resonance imaging
- Risk factors of uterine rupture with a special interest to uterine fundal pressure
- Diagnostic accuracy of fetal scalp lactate for intrapartum acidosis compared with scalp pH
- Reference values for Lactate Pro 2™ in fetal blood sampling during labor: a cross-sectional study
- Linear and non-linear analysis of uterine contraction signals obtained with tocodynamometry in prediction of operative vaginal delivery
- Evaluation of simparteam – a needs-orientated team training format for obstetrics and neonatology
- Transient fetal blood redistribution associated with maternal supine position
- Original articles
- Underlying causes of neonatal deaths in term singleton pregnancies: home births versus hospital births in the United States
- Fourfold increase in prevalence of gestational diabetes mellitus after adoption of the new International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria
- Hematological changes in severe early onset growth-restricted fetuses with absent and reversed end-diastolic flow in the umbilical artery
- Breast milk feeding in infants with inherited metabolic disorders other than phenylketonuria – a 10-year single-center experience
- Clinical significance of a false positive glucose challenge test in patients with a high body mass index
- Obituary
- Obituary – Edward Ogata (1945–2017)
- Congress Calendar
- Congress Calendar
