Oxygen from the lungs and closure of the umbilical arteries

    Spivack (1946) studied the structure and physiology of the umbilical cord,
    and its blood vessels; the infant's heart pumps blood through the umbilical
    arteries to the placenta, which delivers oxygen and nutrients to the baby via
    the umbilical vein.  Spivack observed that the umbilical arteries close quickly
    after onset of respiration, and commented:

    "Oxygenation of the newborn's blood after establishment of
    its pulmonary respiration is the main factor in bringing about
    closure of the umbilical arteries…

    …Experience since long ago has taught some clinicians that
    ligation of the cord is not paramount in the care of the stump."
    [14, p398]

    Ligation of the umbilical cord had come into use as a means to prevent
    bleeding.  However, Spivack cited Engelmann (1883) who noted that the
    umbilical arteries have an intrinsic capacity to check their bleeding in
    unaided labor [15].
   14. Spivack M. The anatomic peculiarities of the human umbilical cord and
        their clinical significance. Am J Obstet Gynecol 1946 Sep; 52(3):387-401.
  15. Engelmann GJ. Labor among primitive peoples. Showing the development
        of the obstetric science of today, from the natural and instinctive customs
        of all races, civilized and savage, past and present. Second edition--
        revised, enlarged and rearranged. Fifty-nine illustrations.  St. Louis, J.H.
        Chambers & Co., 1883
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A decade online (2000-2010)

New Decade
Dr. Morley
Neonatal transition
Dr. Hutchon

Instrument of harm
The first breath
>>Postnatal placental circulation

Comments for the IACC


Conrad Simon (1963-1995)
Pictures (Conrad & his brothers)
Traumatic birth
Death in a group home

© Copyright 1999-2010
Eileen Nicole Simon
Conrad Simon Memorial Research Initiative
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