Biomechanical trade-offs in the pelvic floor constrain the evolution of the human birth canal.

ABSTRACT: Compared with most other primates, humans are characterized by a tight fit between the maternal birth canal and the fetal head, leading to a relatively high risk of neonatal and maternal mortality and morbidities. Obstetric selection is thought to favor a spacious birth canal, whereas the source for opposing selection is frequently assumed to relate to bipedal locomotion. Another, yet underinvestigated, hypothesis is that a more expansive birth canal suspends the soft tissue of the pelvic floor across a larger area, which is disadvantageous for continence and support of the weight of the inner organs and fetus. To test this "pelvic floor hypothesis," we generated a finite element model of the human female pelvic floor and varied its radial size and thickness while keeping all else constant

SUBMITTER: Stansfield E 

PROVIDER: S-EPMC8072325 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature