Mædica – a Journal of Clinical Medicine [613839]

Mædica – a Journal of Clinical Medicine
ORIGINAL PAPER
36 Maedica
A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 MAEDICA – a Journal of Clinical Medicine
2017; 12(1): 36-41
Uterine Artery Doppler Flow Indices
in Pregnant Women During
the 11 Weeks + 0 Days and 13 Weeks
+ 6 Days Gestational Ages:
a Study of 168 Patients
Voicu DASCAU a, Gheorghe FURAUa, Cristian FURAUa, Cristina ONELa,
Casiana STANESCUb, Liliana TATARU a, Cristina GHIB-PARA c, Cristina POPESCUd,
Luminita PILAT e,
Maria PUSCHITAf
aDepartment of Obstetrics and Gynecalogy, „ Vasile Goldiș” Western University, Arad,
Romania
bDepartment of Anatomy, „ Vasile Goldiș” Western University, Arad, Romania
cDepartment of Haematology, „ Vasile Goldiș” Western University, Arad, Romania
dDepartment of Life Sciences, „ Vasile Goldiș” Western University, Arad, Romania
eDepartment of Phsyology, „ Vasile Goldiș” Western University, Arad, Romania
fDepartment of Internal Medicine, „ Vasile Goldiș” Western University, Arad, Romania
Address for correspondence:
Dr. Voicu DASCAU
Address: ??????????????????????????
Email: [anonimizat]
Phone: +????????????
Article received on the 12th of January 2017 and accepted for publication on the 10th of March 2017.ABSTRACT
Objectives: Uterine artery Doppler flow studies during the 11th and 14th week of pregnancy are
important in the prediction of preeclampsia and intrauterine growth restriction in pregnant women as well
as in the prevention thereof.
Methods: Our study on Doppler flow indices of the uterine arteries involved 168 patients examined in
our clinic, with pregnancies ranging from 11 weeks + 0 days to 13 weeks + 6 days.
Results: There were 72 patients from 11 weeks + 0 days to 11 weeks + 6 days (42.86%), 43 from 12 weeks
+ 0 days to 12 weeks + 6 days (25.60%), and 53 from 13 weeks + 0 days to 13 weeks + 6 days (31.55%).
The mean values of the Doppler indices were PI 1.75±0.79, 1.88± 0.81, 1.71±0.81, and 1.58±0.72 and RI
0.72±0.14, 0.75±0.14, 0.71±0.14, and 0.70±0.14 for the entire group and for the three intervals, respectively.
There were 71 (42.26%), 33 (19.64%, with 18 cases or 54.55% on the right side), and 64 (38.10%) patients
with bilateral, unilateral and absent uterine artery notching, respectively. The mean Doppler indices for
the three aforementioned groups were 2.18±0.79, 1.63±0.72, and 1.33±0.57 for the PI, and 0.79±0.11,
0.71±0.14, and 0.66±0.14 for the RI, respectively. The indices for the 175 arteries with and 161 without

UTERINE A RTERY D OPPLER F LOW I NDICES IN P REGNANT W OMEN
37 Maedica A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 INTRODUCTION
Pre-eclampsia (PE) remains one of the
leading causes of maternal and perina-
tal mortality and morbidity, with an es-
timated 10-15% of all maternal deaths
being due to hypertensive diseases in
pregnancy. The prediction of patients at high risk
for PE has been a focus of research and, at pres-
ent, the first trimester is considered to be the
preferred gestational period for PE screening (1).
The prophylactic use of low-dose aspirin begin-
ning in early pregnancy (prior to 16 weeks) is
able to reduce the prevalence of PE by as much
as 50% and significantly decrease rates of perina-
tal death (1). Although no single efficient scree-
ning procedure for predicting PE has been adop-
ted in clinical practice, uterine artery Doppler is
the most widely studied clinical test available for
this particular purpose, becoming a useful meth-
od for the indirect assessment of uteroplacental
circulation in early pregnancy (11–14 weeks). If
combined with examination of maternal history,
mean arterial pressure (MAP) and certain bio-
chemical markers (pregnancy-associated plasma
protein A or PAPP-A and placenta growth factor
or PIGF), uterine artery Doppler may be regard-
ed as an adjunct screening tool for predicting PE
and intrauterine growth restriction (IUGR). Ab-
normal uterine artery Doppler results have been
shown to be strongly correlated with several
types of adverse maternal and perinatal out-
comes (1, 2).
Early identification of pregnant patients at risk
of developing PE and IUGR is more likely to
facilitate targeted antenatal surveillance and
possibly an efficient early intervention. It would
also potentially avoid the development of serious
complications, through interventions such as administration of low-dose aspirin and, if needed,
antihypertensive medication, and early delivery in
selected cases (3-5).
In clinical setting, reference ranges for UtA
Doppler ultrasound during pregnancy are
recommended and used for the appropriate
analysis of impedance to blood flow. In this regard ,
pulsatility index (PI) has been advocated as the
best Doppler index in several studies (6).
Transvaginal approach was used at 11–14 weeks
of gestation, while transabdominal ultrasound was
used at 15–41 weeks. After comparing the
reproducibility of UtA Doppler PI in the first and
second trimesters of pregnancy using both
transvaginal and transabdominal ultrasound scan,
it has been concluded that PI was evenly
significantly higher in both trimesters using
transvaginal approach (2, 7-9).
First and second trimester uterine artery
Doppler blood flow assessments have high
predictive value for clinical outcome (especially i n
the prediction of preeclampsia and IUGR) (10). In
studies which have correlated Doppler velocimetry
and clinical outcomes, a rather wide range of
specificity and sensitivity values were found for
subsequent pregnancy complications (10).
For a correct and clinically significant uterine
artery PI measurement, the gestational age must
be between 11+0 and 13+6 weeks. Trans abdo-
minal ultrasound should be used to obtain a
midsagittal section of the uterus and cervical
canal, and the internal cervical os should be
identified; afterwards, the transducer should be
gently tilted from side to side in each paracervica l
region, using color flow mapping to identify the
uterine arteries as aliasing vessels coursing along
the side of the cervix and uterus. Pulsed wave
Doppler with the sampling gate set at 2 mm to
cover the whole vessel and an angle of insonation notching, taken separately, in all patients, as well as for the uterine arteries with and without notching in
patients with unilateral notching only were 2.16±0.76, 1.30±0.54, 2.08±0.66, and 1.17±0.43 for the PI, and
0.79±0.11, 0.65±0.14, 0.79±0.11, and 0.63±0.12 for the RI, respectively
Conclusions: The mean uterine artery PI and RI decrease from 11 weeks + 0 days-11 weeks + 6 days to
13 weeks + 0 days-13 weeks + 6 days. They also decrease from patients with bilateral uterine artery notching
to those without notching. The frequency of uterine artery notching decreases with increasing gestational
age. Our results are similar to those in literature.
Keywords : pregnancy, gestational age, uterine artery notchi ng, Doppler indices, pulsatility
index, resistivity index, preeclampsia, intrauterin e growth restriction

UTERINE A RTERY D OPPLER F LOW I NDICES IN P REGNANT W OMEN
38 Maedica
A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 <30 ° should be used to obtain flow velocity
waveforms from the ascending branch of the
uterine artery at the point closest to the internal
os. When three similar consecutive waveforms are
obtained, the PI should be measured and the
mean PI of the left and right arteries calculated
(3, 4). q
MATERIAL AND METHODS
We assessed the uterine artery Doppler flow
indices in 168 pregnant patients within
the 11 weeks + 0 days and 13 weeks + 6 days
gestational ages in our clinic during the 2014-
2016 period (both in and outpatients) by using a
Sonoscape SSI-6000 and a General Electric
Logiq e ultrasound devices. The Doppler flow
was analyzed with a 2 mm window and an in-
sonation angle of less than 30 degrees, according
to existing guidelines. q
RESULTS
Among the 168 pregnant women in the group
we studied, there were 72 patients from 11
weeks + 0 days to 11 weeks + 6 days (42.86%),
43 from 12 weeks + 0 days to 12 weeks + 6
days (25.60%), and 53 from 13 weeks + 0 days
to 13 weeks + 6 days (31.55%) gestational age
(Figure 1). The values of the Doppler indices
were 1.75±0.79 (range 0.46-4.33), 1.88± 0.81
(range 0.46-4.33), 1.71±0.81 (range 0.55-4.29),
and 1.58±0.72 (range 0.49-3.93) for the PI and
0.72±0.14 (range 0.36-1), 0.75±0.14 (range 0.36-1), 0.71±0.14 (range 0.40-0.96), and
0.70±0.14 (range 0.37-0.94) for the RI for the
entire group and for the three gestational age in-
tervals, respectively.
Our study revealed that 71 (42.26%), 33
(19.64%), and 64 (38.10%) patients had bilateral,
unilateral and absent uterine artery notching,
respectively (Figure 2). The Doppler indices for
the three aforementioned groups were 2.18±0.79
(range 0.72-4.33), 1.63±0.72 (range 0.55-3.55),
and 1.33±0.57 (range 0.46-2.82) for the PI and
0.79±0.11 (range 0.46-1), 0.71±0.14 (range 0.40-
0.96), and 0.66±0.14 (range 0.36-1) for the RI,
respectively.
After assessing the uterine arteries in the study
group according to the presence or absence of
notching, the indices for the arteries with (n=175,
including 142 in 71 patients with bilateral notchin g
and 33 in 33 patients with unilateral notching) and
without notching (n=161, including 33 in 33 pati-
ents with unilateral notching and 128 in 64 pati-
ents without notching) in all 168 patients, as well
as for the uterine arteries with and without notchi ng
in the 33 patients with unilateral notching, were
2.16±0.76 (range 0.72-4.33), 1.30±0.54 (range
0.46-2.82), 2.08±0.66 (range 0.91-3.55), and
1.17±0.43 (range 0.55-2.09) for the PI and
0.79±0.11 (range 0.46-1), 0.65±0.14 (range 0.36-1),
0.79±0.11 (range 0.52-0.96), and 0.63±0.12
(range 0.40-0.86) for the RI, respectively
Table 1 presents the mean, standard deviations
and the 5th and 95th percentiles for the pulsatilit y
and resistivity indices, while figures 3 and 4 PI RI
Group Value 5th 95 th Value 5th 95 th
All (168 patients) 1.75±0.79 0.55 3.58 0.72±0.14 0.41 0.95
11 weeks + 0 days to 11 weeks + 6 days (72 patients) 1.88± 0.81 0.72 3.34 0.75±0.14 0.50 0.91
12 weeks + 0 days to 12 weeks + 6 days (43 patients) 1.71±0.81 0.79 2.71 0.71±0.14 0.52 0.87
13 weeks + 0 days to 13 weeks + 6 days (53 patients) 1.58±0.72 0.75 2.76 0.70±0.14 0.49 0.89
Bilateral uterine artery notching (71 patients) 2.18±0.79 1.12 3.58 0.79±0.11 0.62 0.93
Unilateral uterine artery notching (33 patients) 1.63±0.72 0.81 2.57 0.71±0.14 0.53 0.86
Absent uterine artery notching (64 patients) 1.33±0.57 0.59 2.36 0.66±0.14 0.43 0.86
Uterine artery with notch (n=175) 2.16±0.76 1.12 3.56 0.79±0.11 0.60 0.93
Uterine artery without notch (n=161) 1.30±0.54 0.58 2.36 0.65±0.14 0.41 0.87
Uterine artery with notch in unilateral notch patients
(n=33)2.08±0.66 1.29 3.16 0.79±0.11 0.62 0.91
Uterine artery without notch in unilateral notch
patients (n=33)1.17±0.43 0.63 2.04 0.63±0.12 0.44 0.81
TABLE 1. Mean PI±SD, mean RI±SD, 5th and 95th percentiles

UTERINE A RTERY D OPPLER F LOW I NDICES IN P REGNANT W OMEN
39 Maedica A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 present the means and the standard deviations
thereof.
Table 2 and Figure 5 show the frequency of
different types of uterine artery notching among
the three gestational age groups (a decrease in the
frequency of both can be observed), while Table 3
and Figure 6 present the distribution of types of
uterine artery notching among the three gestational
age groups (approximately half of the cases with
bilateral or unilateral artery notching are in the 11 FIGURE 1. Age group distribution
FIGURE 3.
Mean PI±DS
FIGURE 4.
Mean RI±DSFIGURE 2. Notch type distributionFIGURE 5. Distribution of frequency of diff erent
types of uterine artery notching among the three
gestational age groups
FIGURE 6. Distribution of types of uterine artery
notching among the three gestational age groups
Notching11 weeks
+ 0 days to
11 weeks +
6 days
(n=72)12 weeks
+ 0 days to
12 weeks +
6 days
(n=43 )13 weeks +
0 days to
13 weeks +
6 days
(n=53)
Bilateral 36 (50%) 17 (39.53%) 18 (33.96%)
Unilateral 16 (22.22%) 8 (18.60%) 9 (16.98%)
Absent 20 (27.78%) 18 (41.86%) 26 (49.06%)
TABLE 2. Distribution of frequency of diff erent
types of uterine artery notching among the three
gestational age groups

UTERINE A RTERY D OPPLER F LOW I NDICES IN P REGNANT W OMEN
40 Maedica
A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 weeks + 0 days to 11 weeks + 6 days gestational
age group).
We used Student’s t-test to compare the PI
and RI among different groups (all patients versus
different gestational age groups and versus groups
according to the presence or absence of notching,
as well as different groups between them, and the
indices of all uterine arteries with and without
notching within the group), the results being
shown in table 4 (NS=non significant) (Table 4).
In the group we studied, uterine artery
notching was always absent in case of PI below
the 5th percentile and RI below the 4 th percentile
and always present in case of PI above the 90th
percentile, while no such percentile could be
established for the RI (there were two patients with an RI of 1 and absent notching). A PI below
0.85 (12 th percentile) yields a FPR (false positive
rate), defined as a present uterine artery notch, o f
2.5%; a PI above 2.77 (11 th percentile) leads to a
FNR (false negative rate), defined as an absent
uterine artery notching, of 5.4%. As for the RI, th e
FPR for a value below 0.53 (11 th percentile) was
8%, while the FNR for a value above 0.91 (94 th
percentile) was 10%. q
DISCUSSION
The frequency of bilateral uterine artery
notching in our study is 42.26% and the frequency
of both bilateral and unilateral uterine artery
notching decrease with increasing gestational age. Notching Bilateral (n=71) Unilateral (n=33) Absent (n=64)
11 weeks + 0 days to 11 weeks + 6 days (n=72) 36 (50.70%) 16 (48.49%) 20 (31.25%)
12 weeks + 0 days to 12 weeks + 6 days (n=43) 17 (23.95%) 8 (24.24%) 18 (28.13%)
13 weeks + 0 days to 13 weeks + 6 days (n=53) 18 (25.35%) 9 (27.27%) 26 (40.62%)
TABLE 3. Distribution of types of uterine artery notching among the three gestational age groups
TABLE 4. Comparison of PI and RIComparison p Comparison p
PI Total vs Bilateral notch <0.0000001 RI Total vs Bilateral notch <0.0000005
PI Total vs Unilateral notch NS RI Total vs Unilateral notch NS
PI Total vs Absent Notch <0.0000001 RI Total vs Absent Notch <0.00005
PI Bilateral notch vs Unilateral notch <0.000005 RI Bilateral notch vs Unilateral notch <0.00005
PI Bilateral notch vs Absent Notch <0.0000001 RI Bilateral notch vs Absent Notch <0.0000001
PI Unilateral notch vs Absent Notch <0.005 RI Unilateral notch vs Absent Notch <0.05
PI Total vs 11 – 11+6 NS RI Total vs 11 – 11+6 <0.05
PI Total vs 12 – 12+6 NS RI Total vs 12 – 12+6 NS
PI Total vs 13 – 13+6 <0.05 RI Total vs 13 – 13+6 NS
PI 11 – 11+6 vs 12 – 12+6 NS RI 11 – 11+6 vs 12 – 12+6 <0.05
PI 11 – 11+6 vs 13 – 13+6 <0.05 RI 11 – 11+6 vs 13 – 13+6 <0.05
PI 12 – 12+6 vs 13 – 13+6 NS RI 12 – 12+6 vs 13 – 13+6 NS
PI Present Notch vs Absent Notch <0.0000001 RI Present Notch vs Absent Notch <0.0000001
PI Present Notch vs Unilateral with
Present Notch NS RI Present Notch vs Unilateral with
Present Notch NS
PI Present Notch vs Unilateral with
Absent Notch <0.0000001RI Present Notch vs Unilateral with
Absent Notch <0.0000001
PI Absent Notch vs Unilateral with
Present Notch <0.0000001RI Absent Notch vs Unilateral with
Present Notch <0.0000005
PI Absent Notch vs Unilateral with
Absent Notch NS RI Absent Notch vs Unilateral with
Absent Notch NS
PI Unilateral with Present Notch vs
Unilateral with Absent Notch <0.0000001RI Unilateral with Present Notch vs
Unilateral with Absent Notch <0.0000005

UTERINE A RTERY D OPPLER F LOW I NDICES IN P REGNANT W OMEN
41 Maedica A Journal of Clinical Medicine, Volume 1 2 No.1 201 7 The results in our study are similar to those in
literature:
–mean PI 1.79, 1.68, 1.58, and 1.49 at
11, 12, 13 and 14, with the 95th
percentile at 2.70, 2.53, 2.38, and
2.24 weeks, respectively (11);
–PI 1.96±0.6, 1.83±0.53, 1.71±0.47,
and 1.58±0.41, with the 95th
percentile at 3.13, 2.88, 2.63, and
2.38 at 11, 12, 13, and 14 weeks,
respectively (12);
–PI 1.6±0.5, 1.5±0.6, 1.4±0.4, and
1.3±0.4 at 11, 12, 13, and 14 weeks,
respectively (1);
–RI 0.7±0.1, 0.7±0.1, 0.6±0.1, and
0.6±0.1 at 11, 12, 13, and 14 weeks,
respectively (1);
–PI 2.32 ± 0.79 and RI 0.83 ± 0.07
with notching, 1.61 ± 0.78 and 0.71
± 0.16 without notching (13);
–95 th percentile of RI at 11-14 weeks at
0.85 (14);
–the frequency of bilateral notching
48.6%, 47.9%, 30.6%, and 28.4% at 11, 12,
13, and 14 weeks, respectively (12). q CONCLUSION
The mean uterine artery PI and RI and the fre-
quency of bilateral and unilateral uterine ar-
tery notching decrease from 11 weeks + 0 days-
11 weeks + 6 days to 13 weeks + 0 days-13
weeks + 6 days. They also decrease from preg-
nant patients with bilateral uterine artery no-
tching to those without notching.
Our aim is to screen, as much as possible, all
pregnant patients between 11 and 14 weeks of
pregnancy who are referring to our clinic of
pregnancy by uterine artery Doppler ultrasound,
in order to discover bilateral notching as soon as
possible for specific prophylactic treatment, accor ding
to existing guidelines and recommendations, to
be started. q
Conflict of interests: none declared.
Financial support: none declared.
1. Alves JA, Silva BY, de Sousa PC, Maia SB,
Costa Fida S. Reference range of uterine
artery Doppler parameters between the
11th and 14th pregnancy weeks in a
population sample from Northeast Brazil.
Rev Bras Ginecol Obstet 2013;35:357-362.
2. Peixoto AB, Da Cunha Caldas TM, Tonni
G, De Almeida Morelli P, Santos LD,
Martins WP, Araujo Júnior E. Reference
range for uterine artery Doppler pulsatility
index using transvaginal ultrasound at
20-24 weeks of gestation in a low-risk
Brazilian population.
J Turk Ger Gynecol Assoc 2016;17:16-20.
3. Poon LC, Syngelaki A, Akolekar R, Lai J,
Nicolaides KH. Combined screening for
preeclampsia and small for gestational age
at 11–13 weeks. Fetal Diagn Ther
2013; 33:16-27.
4. Khalil A, NicolaideS KH. How to record
uterine artery Doppler in the fi rst trimester.
Ultrasound Obstet Gynecol 2013;42:478–479.
5. Roberge S, Nicolaides KH, Demers S,
Villa P, Bujold E. Prevention of perinatal
death and adverse perinatal outcome using
lowdose aspirin: a meta-analysis. Ultrasound Obstet Gynecol 2013;41:491-499.
6. Ferreira AE, Mauad Filho F, Abreu PS,
Mauad FM, Araujo JuniorE, Martins WP.
The reproducibility of fi rst and second
trimester uterine artery pulsatility index by
transvaginal and transabdominal ultra-
sound. Ultrasound Obstet Gynecol
2015;46:546-552. [CrossRef]
J Turk Ger Gynecol Assoc 2016;17:16-20.
7. Scandiuzzi RM, de Campos Prado CA,
Araujo Júnior E, et al. Maternal uterine
artery Doppler in the fi rst and second
trimesters as screening method for
hypertensive disorders and adverse
perinatal outcomes in low-risk pregnancies.
Obstet Gynecol Sci 2016;59:347-356.
8. Ghulmiyyah L, Sibai B. Maternal mortality
from pre¬eclampsia/eclampsia.
Semin Perinatol 2012;36:56-59.
9. Velauthar L, Plana MN, Kalidindi M, et al.
First-trimester uterine artery Doppler and
adverse pregnancy outcome: a meta-analy-
sis involving 55,974 women.
Ultrasound Obstet Gynecol 2014;43:500-507.
10. Akbaș M, Șen C, Calay Z. Correlation
between First and Second Trimester Uterine Artery Doppler Velocimetry and Placental
Bed Histopathology. Int Sch Res Notices
2014;13;2014.
11. Gómez O, Figueras F, Fernández S, et al.
Reference ranges for uterine artery
mean pulsatility index at 11–41 weeks of
gestation. Ultrasound Obst Gyn
2008;32:128-132.
12. Gomez O, Figueras F, Martinez JM, et al.
Sequential changes in uterine artery blood
fl ow pa! ern between the fi rst and second
trimesters of gestation in relation to
pregnancy outcome.
Ultrasound Obstet Gynecol 2006;28:802-808.
13. Gadelha da Costa AG, Spara Patricia,
de Oliveira Costa T, Neto WRT. Uterine
arteries resistance and pulsatility indices at
the fi rst and second trimesters of normal
pregnancies. Radiol Bras 2010;43:161-165.
14. Melchiorre K, Leslie K, Prefumo F, Bhide
A, Thilaganathan B. First-trimester uterine
artery Doppler indices in the prediction of
small-for-gestational age pregnancy and
intrauterine growth restriction.
Ultrasound Obstet Gynecol 2009;33:524-529. R#$#%#&'#*