Spiral arteries (SAs) lie at the interface between the uterus and placenta, and supply nutrients to the placental surface. Maternal blood circulation is separated from the fetal circulation by structures called villous trees. SAs are transformed in early pregnancy from tightly coiled vessels to large high-capacity channels, which is believed to facilitate an increased maternal blood flow throughout pregnancy with minimal increase in velocity, preventing damage to delicate villous trees. Significant maternal blood flow velocities have been theorized in the space surrounding the villi (the intervillous space, IVS), particularly when SA conversion is inadequate, but have only recently been visualized reliably using pulsed wave Doppler ultrasonography. Here, we present a computational model of blood flow from SA openings, allowing prediction of IVS properties based on jet length. We show that jets of flow observed by ultrasound are likely correlated with increased IVS porosity near the SA mouth and propose that observed mega-jets (flow penetrating more than half the placental thickness) are only possible when SAs open to regions of the placenta with very sparse villous structures. We postulate that IVS tissue density must decrease at the SA mouth through gestation, supporting the hypothesis that blood flow from SAs influences villous tree development.

References

References
1.
Pijnenborg
,
R.
,
Dixon
,
G.
,
Robertson
,
W.
, and
Brosens
,
I.
,
1980
, “
Trophoblastic Invasion of Human Decidua From 8 to 18 Weeks of Pregnancy
,”
Placenta
,
1
(
1
), pp.
3
19
.
2.
Pijnenborg
,
R.
,
Vercruysse
,
L.
, and
Hanssens
,
M.
,
2006
, “
The Uterine Spiral Arteries in Human Pregnancy: Facts and Controversies
,”
Placenta
,
27
, pp.
939
958
.
3.
Harris
,
L.
,
2010
, “
Review: Trophoblast-Vascular Cell Interactions in Early Pregnancy: How to Remodel a Vessel
,”
Placenta
,
31
, pp.
S93
S98
.
4.
James
,
J.
,
Whitley
,
G.
, and
Cartwright
,
J.
,
2010
, “
Pre-Eclampsia: Fitting Together the Placental, Immune, and Cardiovascular Pieces
,”
J. Pathol.
,
221
(
4
), pp.
363
378
.
5.
Khong
,
T.
,
de Wolf
,
F.
,
Robertson
,
W.
, and
Brosens
,
I.
,
1986
, “
Inadequate Maternal Vascular Response to Placentation in Pregnancies Complicated by Pre-Eclampsia and by Small-for-Getational-Age Infants
,”
BJOG
,
93
(
10
), pp.
1049
1059
.
6.
Kim
,
Y.
,
Bujold
,
E.
,
Chaiworapongsa
,
T.
,
Gomez
,
R.
,
Yoon
,
B.
,
Thaler
,
H.
,
Rotmensch
,
S.
, and
Romero
,
R.
,
2003
, “
Failure of Physiologic Transformation of the Spiral Arteries in Patients With Preterm Labour and Intact Membranes
,”
Am. J. Obstet. Gynecol
,
189
(
4
), pp.
1063
1069
.
7.
Brosens
,
I.
,
Dixon
,
H.
, and
Robertson
,
W.
,
1977
, “
Fetal Growth Retardation and the Arteries of the Placental Bed
,”
BJOG
,
84
(9), pp.
653
666
.
8.
Burton
,
G.
,
Woods
,
A.
,
Jauniaux
,
E.
, and
Kingdom
,
J.
,
2009
, “
Rheological and Physiological Consequences of Conversion of the Maternal Spiral Arteries for Uteroplacental Blood Flow During Human Pregnancy
,”
Placenta
,
30
(
6
), pp.
473
482
.
9.
Hung
,
T.-H.
,
Skepper
,
J.
, and
Burton
,
G.
,
2001
, “
In Vitro Ischemia–Reperfusion Injury in Term Human Placenta as a Model for Oxidative Stress in Pathological Pregnancies
,”
Am. J. Pathol.
,
159
(
3
), pp.
1031
1043
.
10.
Collins
,
S.
,
Birks
,
J.
,
Stevenson
,
G.
,
Papageorghiou
,
A.
,
Noble
,
J.
, and
Impey
,
L.
,
2012
, “
Measurement of Spiral Artery Jets: General Principles and Differences Observed in Small-for-Gestational-Age Pregnancies
,”
Ultrasound Obstet. Gynecol.
,
40
(
2
), pp.
171
178
.
11.
Collins
,
S.
,
Stevenson
,
G.
,
Noble
,
J.
, and
Impey
,
L.
,
2012
, “
Developmental Changes in Spiral Artery Blood Flow in the Human Placenta Observed With Colour Doppler Ultrasonography
,”
Placenta
,
33
(
10
), pp.
782
787
.
12.
Erian
,
F.
,
Corrsin
,
S.
, and
Davis
,
S.
,
1977
, “
Maternal, Placental Blood Flow: A Model With Velocity-Dependent Permeability
,”
J. Biomech.
,
10
(
11
), pp.
807
814
.
13.
Chernyavsky
,
I.
,
Jensen
,
O.
, and
Leach
,
L.
,
2010
, “
A Mathematical Model of Intervillous Blood Flow in the Human Placentome
,”
Placenta
,
31
(
1
), pp.
44
52
.
14.
Lecarpentier
,
E.
,
Bhatt
,
M.
,
Bertin
,
G.
,
Deloison
,
B.
,
Salomon
,
L.
,
Deloron
,
P.
,
Fournier
,
T.
,
Barakat
,
A.
, and
Tsatsaris
,
V.
,
2016
, “
Computational Fluid Dynamic Simulations of Maternal Circulation: Wall Shear Stress in the Human Placenta and Its Biological Implications
,”
PloS One
,
11
(
1
), p.
e0147262
.
15.
Brosens
,
I.
, and
Dixon
,
H.
,
1966
, “
The Anatomy of the Maternal Side of the Placenta
,”
BJOG
,
73
(
3
), pp.
357
363
.
16.
Lyall
,
F.
,
2005
, “
Priming and Remodeling of Human Placental Bed Spiral Arteries During Pregnancy—A Review
,”
Placenta
,
26
(
Suppl. A
), pp.
S31
S36
.
17.
de Paula
,
C. F. S.
,
Ruano
,
R.
,
Campos
,
J. A. D. B.
, and
Zugaib
,
M.
,
2008
, “
Placental Volumes Measured by 3-Dimensional Ultrasonography in Normal Pregnancies From 12 to 40 Weeks Gestation
,”
J. Ultrasound Med.
,
27
(
11
), pp.
1583
1590
.
18.
Boyd
,
J.
, and
Hamilton
,
W.
,
1970
,
The Human Placenta
,
Heffer and Sons
,
Cambridge, UK
.
19.
Konje
,
J. C.
,
Huppertz
,
B.
,
Bell
,
S. C.
,
Taylor
,
D. J.
, and
Kaufmann
,
P.
,
2003
, “
3-Dimensional Colour Power Angiography for Staging Human Placental Development
,”
Lancet
,
362
(
9391
), pp.
1199
1201
.
20.
Boyd
,
J.
, and
Hamilton
,
W.
,
1967
, “
Development and Structure of the Human Placenta From the End of the 3rd Month of Gestation
,”
BJOG
,
74
(
2
), pp.
161
226
.
21.
Pries
,
A.
,
Secomb
,
T.
, and
Gaehtgens
,
P.
,
1996
, “
Biophysical Aspects of Blood Flow in the Microvasculature
,”
Cardiovasc. Res.
,
32
(
4
), pp.
654
667
.
22.
Chernyavsky
,
I. L.
,
Leach
,
L.
,
Dryden
,
I. L.
, and
Jensen
,
O. E.
,
2011
, “
Transport in the Placenta: Homogenizing Haemodynamics in a Disordered Medium
,”
Philos. Trans. R. Soc. London A
,
369
(
1954
), pp.
4162
4182
.
23.
Mayhew
,
T.
,
1997
, “
Recent Applications of the New Stereology Have Thrown Fresh Light on How the Human Placenta Grows and Develops Its Form
,”
J. Microsc.
,
186
(
2
), pp.
153
163
.
24.
Hasegawa
,
J.
,
Arakawa
,
K.
,
Nakamura
,
M.
,
Matsuoka
,
R.
,
Ichizuka
,
K.
, and
Katsufumi
,
O.
,
2011
, “
Analysis of Placental Weight Centiles Is Useful to Estimate Cause of Fetal Growth Restriction
,”
J. Obstet. Gynecol. Res.
,
37
(
11
), pp.
1658
1665
.
25.
Collins
,
L. S.
,
2011
, “
Development of Placental Ultrasound Markers to Screen for the Term, Small for Gestational Age (SGA) Baby
,” Ph.D. thesis, Faculty of Medical Sciences, University of Oxford, Oxford, UK.
26.
Junaid
,
T.
,
Brownbill
,
P.
,
Chalmers
,
N.
,
Johnstone
,
E.
, and
Aplin
,
J.
,
2014
, “
Fetoplacental Vascular Alterations Associated With Fetal Growth Restriction
,”
Placenta
,
35
(
10
), pp.
808
815
.
27.
Wong
,
H.
, and
Cheung
,
Y.
,
2010
, “
Sonographic Study of the Decidua Basalis in Early Pregnancy Loss
,”
Ultrasound Obstet. Gynecol.
,
36
(
3
), pp.
362
367
.
28.
Schild
,
R. L.
,
Knobloch
,
C.
,
Dorn
,
C.
,
Fimmers
,
R.
,
Van Der Ven
,
H.
, and
Hansmann
,
M.
,
2001
, “
Endometrial Receptivity in an In Vitro Fertilization Program as Assessed by Spiral Artery Blood Flow, Endometrial Thickness, Endometrial Volume, and Uterine Artery Blood Flow
,”
Fertil. Steril.
,
75
(
2
), pp.
361
366
.
29.
Durnwald
,
C. P.
, and
Mercer
,
B. M.
,
2008
, “
Myometrial Thickness According to Uterine Site, Gestational Age, and Prior Cesarean Delivery
,”
J. Matern.-Fetal Neonat. Med.
,
21
(
4
), pp.
247
250
.
30.
Degani
,
S.
,
Leibovitz
,
Z.
,
Shapiro
,
I.
,
Gonen
,
R.
, and
Ohel
,
G.
,
1998
, “
Myometrial Thickness in Pregnancy: Longitudinal Sonographic Study
,”
J. Ultrasound Med.
,
17
(
10
), pp.
661
665
.
31.
Blevins
,
R. D.
,
1984
,
Applied Fluid Dynamics Handbook
,
Van Nostrand Reinhold
,
New York
.
32.
Wigglesworth
,
J.
,
1969
, “
Vascular Anatomy of the Human Placenta and Its Significance for Placental Pathology
,”
BJOG
,
76
(
11
), pp.
979
989
.
33.
Reynolds
,
S.
,
1972
, “
On Growth and Form in the Hemochorial Placenta: An Essay on the Physical Forces That Shape the Chorionic Trophoblast
,”
Am. J. Obstet. Gynecol.
,
114
(
1
), pp.
115
132
.
34.
Reynolds
,
S.
,
1966
, “
Formation of Fetal Cotyledons in the Hemochorial Placenta
,”
Am. J. Obstet. Gynecol.
,
94
(
3
), pp.
425
439
.
35.
Benirschke
,
K.
,
Kaufmann
,
P.
, and
Gilbert-Barness
,
E.
,
1996
,
Pathology of the Human Placenta
, Vol.
120
,
American Medical Association
,
Chicago, IL
.
36.
Leiser
,
R.
,
Kosanke
,
G.
, and
Kaufmann
,
P.
,
1991
, “
Human Placental Vascularization
,”
Placenta: Basic Research for Clinical Application
,
Karger
,
Basle, Switzerland
.
37.
Hutchinson
,
E.
,
Brownbill
,
P.
,
Jones
,
N.
,
Abrahams
,
V.
,
Baker
,
P.
,
Sibley
,
C.
, and
Crocker
,
I.
,
2009
, “
Utero-Placental Haemodynamics in the Pathogenesis of Pre-Eclampsia
,”
Placenta
,
30
(
7
), pp.
634
641
.
38.
Jackson
,
M.
,
Walsh
,
A.
,
Morrow
,
R.
,
Mullen
,
J.
,
Lye
,
S.
, and
Richie
,
J.
,
1995
, “
Reduced Placental Villous Tree Elaboration in Small-for-Gestational-Age Pregnancies: Relationship With Umbilical Artery Doppler
,”
Am. J. Obstet Gynecol.
,
172
(
2
), pp.
518
525
.
39.
Harris
,
J.
, and
Ramsey
,
E.
,
1966
,
The Morphology of Human Uteroplacental Vasculature
, Carnegie Institution of Washington, Washington, DC, pp. 43–58.
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