HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by REYNOLDS, S. R. M. Search for Related Content PubMed PubMed Citation Articles by REYNOLDS, S. R. M.

MECHANISMS OF PLACENTOFETAL BLOOD FLOW

From the Department of Anatomy at the University of Illinois College of Medicine, Chicago, Illinois.

The average length of the umbilical cord at delivery is 21 ± 1 in., but lengths vary from 10 to 50 in. When distended and carrying blood between the fetus and the placenta, the cord is longer; the distended arteries and vein are spiraled about each other. No physiologic data explain the manner by which blood flows from the placenta to fetus. When pressures (60–80 mmHg in arteries; 10–20 mmHg in the vein) are recorded simultaneously, arterial pulse pressure has been observed to rise and umbilical vein pressure to fall. They are 180 degrees out of phase. When necessary physical factors are taken into account, it is found that the system satisfies all requirements of a pump known as one of the pulsometer type. This system is one that is widely used by engineers, but it is unique among physiologic systems.

This article has been cited by other articles:

				Z. Gordon, O. Eytan, A. J. Jaffa, and D. Elad Hemodynamic analysis of Hyrtl anastomosis in human placenta Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2007; 292(2): R977 - R982. [Abstract] [Full Text] [PDF]

				M. W. M. de Laat, A. Franx, M. L. Bots, G. H. A. Visser, and P. G. J. Nikkels Umbilical coiling index in normal and complicated pregnancies. Obstet. Gynecol., May 1, 2006; 107(5): 1049 - 1055. [Abstract] [Full Text] [PDF]