ArticleBMC biology2021
The evolution of pelvic canal shape and rotational birth in humans.
Article in BMC biology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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Who cites it
15 citing papers in PubMed, 29 citations in OpenAlex.
- Humans are not unique: difficult birth is common in placental mammals.Biological reviews of the Cambridge Philosophical Society · 2026Review
- Insights into Neanderthal development, childbirth, and locomotion from the Palomas and Dederiyeh pelves.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Testing the limits: the impact of extreme functional hip width on the muscular demands of walking.Biology open · 2026Article
- Bony birth canal and pelvic organ prolapse: a quantitative assessment for dimensions of pelvic midplanes based on MRI.Abdominal radiology (New York) · 2025Article
- Pelvic shape predisposes for pelvic organ prolapse: a geometric morphometry study.Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology · 2025Article
- Pelvic ring ratio: a novel indicator of comprehensive pelvic alignment assessment.Asian spine journal · 2025Article
- Comprehensive Analysis of the Biomechanical Research of Pelvic Organ Prolapse: A Scientometric Approach.Journal of multidisciplinary healthcare · 2025Article
- Finite element modeling in obstetrics and gynecology: advances, applications, and challenges.Frontiers in medicine · 2025Review
- No birth-associated maternal mortality in Japanese macaques (Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- Reconsidering the developmental origins of adult disease paradigm: The 'metabolic coordination of childbirth' hypothesis.Evolution, medicine, and public health · 2024Review
- There is an obstetrical dilemma: Misconceptions about the evolution of human childbirth and pelvic form.American journal of biological anthropology · 2023Review
- Article
- Birth, love, and fear: Physiological networks from pregnancy to parenthood.Comprehensive psychoneuroendocrinology · 2022Review
- Variation in human 3D trunk shape and its functional implications in hominin evolution.Scientific reports · 2022Article
- The evolution of pelvic canal shape and rotational birth in humans.BMC biology · 2021Article
Corrections and comments
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Authors and funding
5 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe human foetus typically needs to rotate when passing through the tight birth canal because of the complex shape of the pelvis. In most women, the upper part, or inlet, of the birth canal has a round or mediolaterally oval shape, which is considered ideal for parturition, but it is unknown why the lower part of the birth canal has a pronounced anteroposteriorly oval shape.
resultsHere, we show that the shape of the lower birth canal affects the ability of the pelvic floor to resist the pressure exerted by the abdominal organs and the foetus. Based on a series of finite element analyses, we found that the highest deformation, stress, and strain occur in pelvic floors with a circular or mediolaterally oval shape, whereas an anteroposterior elongation increases pelvic floor stability.
conclusionsThis suggests that the anteroposterior oval outlet shape is an evolutionary adaptation for pelvic floor support. For the pelvic inlet, by contrast, it has long been assumed that the mediolateral dimension is constrained by the efficiency of upright locomotion. But we argue that the mediolateral elongation has evolved because of the limits on the anteroposterior diameter imposed by upright posture. We show that an anteroposteriorly deeper inlet would require greater pelvic tilt and lumbar lordosis, which compromises spine health and the stability of upright posture. These different requirements of the pelvic inlet and outlet likely have led to the complex shape of the pelvic canal and to the evolution of rotational birth characteristic of humans.
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