Reasons For Predominance
The piriform (pear-shaped) morphology of the uterus has been given as the major cause for the finding that most singletons favor the cephalic presentation at term. The fundus is larger and thus a fetus will adapt its position so that the bulkier and more movable podalic pole makes use of it, while the head moves to the opposite site. Factors that influence this positioning include the gestational age (earlier in gestation breech presentations are more common as the head is relatively bigger), size of the head, malformations, amount of amniotic fluid, presence of multiple gestations, presence of tumors, and others.
Two-thirds of all vertex presentations are LOA, possibly because of the asymmetry created by the descending colon that is on the left side of the pelvis.
Read more about this topic: Cephalic Presentation
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“Here we also see: what this divinity lacks is not only a sense of shame—and there are also other reasons for conjecturing that in several respects all of the gods could learn from us humans. We humans are—more humane.”
—Friedrich Nietzsche (1844–1900)
“Here we also see: what this divinity lacks is not only a sense of shame—and there are also other reasons for conjecturing that in several respects all of the gods could learn from us humans. We humans are—more humane.”
—Friedrich Nietzsche (1844–1900)
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