IUGR, AFI, and Aneuploidy
IUGR
Anomalies
Poly
X
X
7%
X
X
X
Aneuploid
X
32 %
X
27 %
X
47 %
Doppler
IUGR: Maternal Doppler
• Uterine artery:
– S/D > 2.6 associated with IUGR, IUFD
– Elevated resistance index and IUGR:
• 70.6% sensitive
• 33.3% PPV
IUGR: Fetal Dopplers
• Umbilical:
– rising S/D ratio = increasing placental
resistance
– associated with fewer small arteries of tertiary
placental villi
• Falling pulsatility index in head:
– indicates increased flow to brain
• Venous Dopplers:
– Cardiovascular performance
IUGR: Fetal Dopplers
• Study of 43 IUGR fetuses:
– 85% had S/D ratios > 95th percentile
– decreased diastolic flow indicating high
placental flow resistance
• Trudinger et al., Br J Obstet Gynaecol 92:39, 1985
IUGR: Dopplers and Outcome
• When umbilical S/D known:
– lower PNM rates, fewer antenatal admissions,
fewer inductions, fewer C/S
– no improvement noted for low risk pregnancies
• Divon & Ferber, Perinat Neonat Med 5:3, 2000
Absent/Reversed EDV Doppler
Absent/Reversed EDV Doppler
•
•
•
•
•
80% will have IUGR
36% PNM rate
REDV: >70% placental arteries obliterated
Mean time to delivery 7 days (0-49)
Management:
– BMS, hospital bed rest, intensive monitoring,
liberal delivery
– venous Dopplers
MCA Doppler Technique
• Obtain axial section of the brain, including
the thalami and the CSP. Sweep lower.
• The circle of Willis is visualized.
• MCA of one side is examined close to its
origin from the internal carotid artery.
• The angle of insonance is kept as close as
possible to 0 degrees.
MCA Doppler: Dual Uses
• Fetal circulatory redistribution
– Pulsatility index, S/D ratio
• Fetal anemia
– Peak systolic velocity
IUGR: Middle Cerebral Doppler
• Normally demonstrates low diastolic flow
• Increased diastolic flow:
– possible early indicator of fetal hypoxemia
(Gudmundsson, 1996)
– Sign of cerebral redistribution with chronic
hypoxemia (brain sparing effect)
(Wladimiroff, 1986; Mari, 1992; Gramellini, 1992)
IUGR: Middle Cerebral Doppler
Normal MCA
Abnormal MCA
IUGR: Value of Doppler
• SGA fetuses with:
– Normal AFV
– Normal UmA S/D
– Normal MCA Dopplers
– >97% NPV for major negative perinatal
sequellae
• Fong et al., Radiology 213:681, 1999.
Fetal Venous Circulation
Central Venous Circulation
• Doppler flow waveforms
– Fetal venous system has characteristic pulsations
which reflect CVP
Normal Venous Dopplers
DV
UV
Abnormal Venous Dopplers
DV
UV
IUGR: Venous Dopplers
AEDV + umbilical vein pulsations = 54% mortality
AEDV - umbilical vein pulsations = 10% mortality
Indik, Obstet Gynecol 77:551, 1991
Venous atrial back flow waves are suggestive of metabolic
Acidemia documented by PUBS
Hecher et al., Am J Obstet Gynecol 173:10, 1995
Fetal Diagn Ther. 2012;32(1-2):116-22
IUGR: Fetal Response to UPI
Respiratory/Metabolic
Dysfunction
Hypoxia and
Hypercarbia
Compensation
Shunting:
To: brain, heart, adrenal
From: lungs, bowel, kidney
Ultrasound/Doppler:
Oligohydramnios
UmA and MCA Dopplers
Acidosis
Decompensation
High right atrial pressure
DV dilatation
Myocardial dysfunction
Doppler:
venous/cardiac changes
BPP abnormal
IUGR: Fetal Well-Being
• BPP use with IUGR:
– strong association with cord pH
– cascade of decompensation:
pH
NR NST
No FBM
Movement
Tone
Dead Man Float
– BPP: lower rates of intervention compared to
OCT/CST, with equal outcomes
Percent
Doppler Findings With BPP < 6
100
90
80
70
60
50
40
30
20
10
0
BPP
UAEDF/RF
DV
MCA
IVC
UVP
-7
-5.5
-4
-2.5
-1
Delivery
Days to Delivery
Baschat, Ultrasound Obstet Gynecol 18:571, 2001
Trends in Variables Before Delivery at <32 wks
DV
BTBV
Hecher, Ultrasound Obstet Gynecol 18:564, 2001
IUGR: Therapy
• Aspirin
– ASA + dipyridamole from 16 weeks in women
with Hx of IUGR
– Treatment: 13% IUGR, no severe IUGR
– No Tx:
61% IUGR, 27% server IUGR
• Wallenburg, Am J Obstet Gynecol 157:1230, 1987
– Meta-analysis on 50-100 mg ASA
• significant reduction of IUGR noted
• Br J Obstet Gynecol 104:450, 1997
IUGR: Timing of Delivery
“The majority of fetal deaths occur after the 36th week
of gestation and before labor which leads to the conclusion that
many deaths could be prevented by accurate recognition of
growth restriction and appropriately timed and conducted
intervention.”
Frigoletto, Clin Obstet Gynecol, 1977
IUGR: Long Term Morbidity
• The potential for normal long term growth
is positive
– late developing IUGR: excellent
– early, prolonged IUGR: risk of suboptimal size
(e.g. 50% with small HC have HC < 10th
percentile at 8 years).
IUGR: Neurologic Outcome
• Depends:
–
–
–
–
degree of IUGR, especially small HC
timing of onset
GA at delivery
postnatal care
• CP risk is increased 4-6 times, for IUGR
between 32-42 weeks
– Jarvis, Lancet. 2003 Oct 4;362(9390):1106-11
IUGR: Adult Disease
• Barker Hypothesis
– England/Wales 1901-1910, areas with high infant
mortality correlated with CAD in men aged 35-74
in the 1960s-70s
– Theory: LBW survivors might have more CAD
– Birth records:
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•
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•
•
BW < 5.5 lbs: 3 times number of deaths from CAD
HTN and CVA also increased
Greatest risk: LBW, small HC, short, small placentas
Also more: abdominal obesity, AODM, hyperlipidemia
Cause: pancreatic/adrenal insuff, sympath. dysfx?