National Ribat University
Faculty of Graduate Studies & Scientific Research
Accuracy of Ultrasound Estimation of Fetal Weight
in Normal Vaginal Deliveries at Almuglad Hospital
West Kordofan State-Sudan
A Thesis Submitted in Partial Fulfillment of The Degree
of M.Sc. In diagnostic ultrasound
By: Elnazeer Abd Almonem Hashim Abd Almonem
Supervisor: Dr. Elsir Ali Saeed
Apr 2015
1
Dedication
To my mother and father for their unlimited support
I
Acknowledgement
I would like to thank the following people and institutions whom in one way or
another had been instrumental for the completion of this research endeavor by their
invaluable support and unending encouragement:
I would like to thank the College of higher studies (National Ribat University)
for their continuous support during teaching days. We are highly indebted to Dr. Elsir
Ali Saeed the director of Afro-Asian centre for training of medical sciences
(AACMS) without whose auspices this material would have not been written. In
particular, am very grateful to him as he is also my supervisor for his uninterrupted
follow up, supervision, encouragement and critical reviews and valuable comments on
the initial drafts and final work. I would like to extend my gratitude and appreciation
to Dr. Mohamed Ahmed, the medical director of Al muglad hospital and Dr. Izzat
Younis the obstetrician in that hospital for their welcome and facilitation to reach
information sources, access to the files and sonographic examination of patients
without who’s this work would have not been written.
Also I would like to thank the mid-wives Um Salama Mohammed and Zainab
Norig for assisting me in weighing newborns. Great thanks to Abdalatif Mohammed
for his work in data entry and analysis.
Finally I would like to thank ministry of
health west kordofan state for permission to conduct the study. To all the above
people, my sincere thanks and love and I wish you all the strength in your endeavors;
may people show you as much care and help as you have shown me.
II
List of Figures
Figure 1 ……………………………….…………………………………………...35
Figure 2 ……………………………………….………………..………………….36
Figure 3 ………………………………………….………………...………………37
Figure 4 …………………………………….……………………………..……….38
Figure 5 …………..……………………….……………………………………….39
Figure 6 ……………………………………….………..………………………….40
Figure 7 ……………………………………………………….……….…………..41
Figure 8 ……………………………………………………...…………………….42
Figure 9 ……………………………………………………....……………………44
Figure 10 …………………………………………………….……………….……46
Figure 11 ………………………………………………..………………………....47
Figure 12 ……………………………………………….………………………….48
III
List of Tables
Table No. 1 …………………….………………………………...…………………..35
Table No. 2…………………...………………………………...…………………….36
Table No.3 …………………………………………………...………………………37
Table No. 4……………………………………………..…….………………………38
Table No.5 ………………………………………………………………………..….39
Table No. 6. ……………………………………………………………………….....40
Table No. 7………………………………………………………………………...…41
Table No 8. ……………………………………………..……………………………43
Table No. 9. …………………………………………………………..…….………..43
Table No. 10. .………………………………………………………………………..44
Table No. 11. ………………………………………………….……………………..45
Table No. 12. .……………………………………………..……………………..…. 46
Table No 13. …………………………………………………………….…….……..48
Table No. 14.…………………………………………………….…….……………..48
Table No. 15.…………………………………………………………………………49
Table No. 16 ……………………………………………………….………………...50
IV
List of Abbreviations
AC
abdominal circumference
AFW
actual fetal weight
AGA
appropriate for gestational age
BW
birth weight
BPD
biparietal diameter
CR/CRL crown rump length
EFW
estimated fetal weight
HC
head circumference
IUGR
intrauterine growth restriction
LGA
large for gestational age
FL
femur length
FWE
fetal weight estimation
GDM
gestational diabetes mellitus
OFD
occipito-frontal diameter
SGA
small for gestational age
VLBW
very low birth weight
PKU
Phenylketonuria
V
SD
standard deviation
TORCH
Toxoplasmosis, Other (syphilis, varicella-zoster, parvovirus B19), Rubella,
Cytomegalovirus (CMV), and Herpes infections
VI
Abstract
Objective:
The objective of this study was to assess the accuracy of ultrasound estimation of
fetal weight in normal vaginal deliveries at Almuglad hospital.
Methods:
The study was a prospective cross sectional study with sample group of 74
pregnant ladies delivered normally in Almuglad hospital from Jan – Apr 2015. Fetal
weight was estimated by Hadlock and shephards formula within one week prior to
delivery and then newborn weight taken within 24 hours after delivery. The
information was collected and data was analyzed by using SPSS and Kruskal Wallis
Test (post-hoc analysis) Pearson’s correlation coefficient within 95% confidence
interval p values <0.05 were considered as statistically significant.
Results:
There are no significant differences between means for EFW by Hadlock and
shephards or Hadlock and AFW or shephards and AFW .The correlation was
significant for all fetal weights, but the correlation between EFW by Hadlock and
AFW is greater than the correlation between EFW by shephards and AFW which
means the EFW by Hadlock is better than EFW by shephards.
Conclusion:
The correlation of EFW by Hadlock and AFW is greater than the correlation of
EFW by shephards and AFW which means that the EFW by Hadlock is better than
EFW by shephards. So using Hadlock formula is more accurate in estimation of fetal
weight by sonography.
VII
‫مستخلص الدراسة‬
‫الهدف ‪:‬‬
‫هذفج اىذساست اىى حقييٌ دقت اىَىجاث فىق اىصىحيت فى حقذيش وصُ اىجْيِ فى حاىت اىىالداث اىطبيؼيت‬
‫فى ٍسخشفى اىَجيذ‪.‬‬
‫طريقة البحث‪:‬‬
‫ماّج اىذساست ٍقطؼيت حيث حٌ ححذيذ ػذد ‪ 47‬حاىت حَو باىىالدة اىطبيؼيت مؼيْت ىيبحث فى ٍسخشفى‬
‫اىَجيذ فى اىفخشة ٍِ يْايشحخى ابشيو ‪ .5102‬حٌ حقذيش وصُ اىجْيِ خاله اسبىع قبو اىىالدة باسخخذاً ٍؼادىخى‬
‫هادىىك وشيفاسد ‪ ,‬ثٌ ححذيذ وصُ اىجْيِ خاله ‪ 57‬ساػت بؼذ اىىالدة‪ .‬بؼذ جَغ اىبياّاث حٌ ححيييها بىاسطت ّظاً‬
‫ححييو اىحضً االحصائيت حيث اػخبش ٍؼاٍو اسحباط بيشسىُ فى غضىُ ‪ %52‬يحَو دالىت احصائيت‪.‬‬
‫النتائج‪:‬‬
‫ىٌ حىجذ فشوقاث راث دالىت احصائيت بيِ ٍخىسطاث حقذيش وصُ اىجْيِ باسخخذاً ٍؼادىت هادىىك‬
‫وشيفاسد او ها دىىك واىىصُ اىحقيقي ىيجْيِ او شيفاسد واىىصُ اىحقيقي ىيجْيِ‪ٍ .‬ؼاٍو االسحباط ماُ ٍؼخبشا ىنو‬
‫حقذيشاث وصُ اىجْيِ حيث ٍؼاٍو االسحباط فى حقذيش وصُ اىجْيِ باسخخذاً ٍؼادىت هادىىك واىىصُ اىحقيقي ماُ‬
‫امبش ٍِ ٍؼاٍو االسحباط باسخخذاً شيفاسد واىىصُ اىحقيقي‪ ,‬ىزىل ٍؼادىت هادىىك هى االفضو ىخقذيش وصُ اىجْيِ‪.‬‬
‫الخالصة ‪:‬‬
‫ٍؼاٍو االسحباط ماُ ٍؼخبشا ىنو حقذيشاث وصُ اىجْيِ حيث ٍؼاٍو االسحباط فى حقذيش وصُ اىجْيِ‬
‫باسخخذاً ٍؼادىت هادىىك واىىصُ اىحقيقي ماُ امبش ٍِ ٍؼاٍو االسحباط باسخخذاً شيفاسد واىىصُ اىحقيقي‪ ,‬ىزىل‬
‫ٍؼادىت هادىىك هى االفضو ىخقذيش وصُ اىجْيِ‪ .‬ىزىل اسخخذاً ٍؼادىت هادىىك امثش دقت فى حقذيش وصُ اىجْيِ‬
‫باسخخذاً اىَىجاث فىق اىصىحيت‪.‬‬
‫‪VIII‬‬
List of contents
Page
Dedication ……………………………………...…..…………………………………ii
Acknowledgment………………………………………...………………………….. iii
List of figures ……………………………………..……...…………………………. iv
List of tables...................................................................................................................v
List of abbreviations ……………………………………………...………………….
IX
Abstract……………………………………………………………………………...IXi
CHAPTER I Introduction
1-1 Background information ……………………….…………...………………….. 1
1-1-1 Embryology and Anatomical aspects……………………….…………….2
1-1-2 Pathophysiology ………………………………….………………………4
1-2 Problem Statement………………………………............................................... 12
1-3 Justification ……...................................................................................................16
1-4 Objectives of the Study ……………….….……………………..……………… 17
1-4-1 General objective ………………………………………...……………. 17
1-4-2 Specific objectives ………………………..…………..…………………17
1-5 Literature review.............................................................................................…...18
IX
CHAPTER 2 Research methods
2-1 Type of study.........................................................................................................27
2-2 Study area..............................................................................................................27
2-3 Study population ...................................................................................................28
2-3-1 Inclusion criteria …………………………………………………………28
2-3-2 exclusion criteria.........................................................................................28
2-4 Sampling (Type, size, frame, technique)………………………..…………….....28
2-5 Data collection.......................................................................................................29
2-6 Data analysis..........................................................................................................30
2-7 Ethical consideration..............................................................................................31
CHAPTER 3 Results & Discussion
3-1 Results ……………………………………………………………..…………….32
3-1-1 Statistical analysis …………………………………………….……………33
3-1-2 Comparison of expected fetal weight by different methods …….…………43
3-2 Discussion……………………………………………..………………………... 52
3-2-1 Age group distribution, Gravidity and parity….………………...………..52
3-2-2 GA distribution and estimated fetal weight by Hadlock and shephards and
actual fetal weight ……………………………………….…………………………..53
X
3-2-3 Correlation between Estimated fetal weight by Hadlock, shephards and
actual fetal weight ……………………………………...……………………………54
CHAPTER 4 conclusions
4-1 Conclusions………………………………………………………………………55
4-2 Recommendations ……………………………………………………………….56
References…………………………………………………..………………………..57
Annexes …………………………………………………………………………….
XI
Chapter 1: Introduction
XII
1- Introduction
1-1 Background information
The ultrasound estimation of fetal weight in term pregnancies is used to determine
growth, and this may affect the timing and route of delivery
(1)
.
Accurate prenatal
estimation of fetal weight (EFW) in late pregnancy and labour is extremely useful in
the management of labour and delivery, permitting obstetricians to make decisions
about instrumental vaginal delivery, trial of labour after caesarean delivery and
elective caesarean section for patients suspected of having a macrosomic fetus
(2)
.An
accurate diagnosis of macrosomia for patients with gestational diabetes can reduce
perinatal morbidity as it may assist the physician and staff in deciding the appropriate
route of delivery to prepare for shoulder dystocia or to prevent a traumatic injury
(3)
.
Correct EFW values are also important when intrauterine growth is restricted and in
preterm labour
(4)
. So, accurate estimation of fetal weight has paramount importance
in routine antenatal care and for detection of fetal growth abnormalities which is
essential in management of labor and delivery (10).
The perinatal complications associated with low birth weight are most often
attributable to fetal prematurity, but may sometimes also arise as the result of
intrauterine growth restriction. For macrosomic fetuses, potential complications
associated with delivery include shoulder dystocia, brachial plexus injuries, bony
injuries, and intrapartum asphyxia, as well as maternal risks that include birth canal
injuries, pelvic floor injuries damage, and postpartum hemorrhage. The occurrence of
cephalopelvic disproportion is more prevalent with increasing fetal size and
contributes to an increased rate of both operative vaginal delivery and cesarean
delivery for macrosomic fetuses compared with fetuses of normal weight(9)
1
1-1-1 Embryology and Anatomical aspects
Fertilized oocyte quickly develops into a blastocyst, in which the embryo itself
is represented by embryoblast, which will soon turn into an embryonic disc. The disc
becomes oval and from the end of the 3rd week it begins to bend in the craniocaudal
and also dorsoventral axis and finally becomes the cylindrical embryo body. The
somite stage of development follows. The embryo is bent, it has the shape of the
letter C, and the convexity is dorsal. In a very large head part, there is the forebrain
with a frontal prominence, then (dorsally from the forebrain) midbrain (mesencefalon)
with a dorsal curve (flexura cephalica). Another bend forms flexura occipitalis in the
hindbrain region. On the concave dorsal side of the embryo body somites are plainly
visible. Caudal end of the embryo body is also ventrally bent and ends with a tail. On
the ventral side of the body there are the heart and liver prominences. Face and limb
prominences begin to form (the limbs resemble tiny fins). At the end of the first lunar
month, the body is 4 mm long (53).
In the 2nd lunar month, development of the facial structures continues — eyes,
ears and nose are formed. The body begins to straighten and the head rounds out. In
the brain the 4th ventricle is formed. The tail is shorter. Limbs continue to develop,
fingers become separate. The neck begins to form and also the insertion of the
umbilical cord narrows. The genitalia prominence is being formed. Slowly embryo
gains human features and becomes distinguishable from embryos of other mammals.
The crown to rump length at the end of the 2nd month is approximately 28 mm. At
this stage, terminology changes and the embryo becomes fetus.
In the 3rd lunar month the fetus continues to grow quickly, most of the internal
organs are in their final positions. Its trunk lengthens, but the head still remains rather
2
large compared to the rest of the body (the head is approx. 1/3 of body length).
External genitalias are completely developed and gender can be told. Body length at
the end of the 2nd month is 90 mm, CR length 70 mm. The fetus weights
approximately 20 g.
In the 4th month rapid growth continues, nails begin to appear and skin is covered
with first (very fine) hair (lanugos). The body is about 150 mm long, CR length is
130 mm, and weight is approx. 120 g (53).
In the 5th lunar month growth slows down, the head becomes smaller compared
to the rest of the body. The fetus is covered with lanugos, vernix caseosa is produced.
The fetus moves and its mother begins to feel its movement — primigravida around
19th wks, multigravida approx. 2 weeks earlier. Heartbeat can be detected with a
stethoscope. Body length at the end of the month is 250 mm, CR is 180 mm, weight is
approximately 300 g(53).
In the 6th lunar month because there is no subcutaneous fat, the skin is soft,
transparent, purple-red with blood vessels clearly visible. The head is covered with
short hair, eye lashes and eyebrows begin to grow. Body length at the end of the
month is 300 mm, CR is 230 mm, and weight is approximately 600 g (53).
In the 7th lunar month subcutaneous fat begins to form, skin stretches Eyes open;
epithelial suture between eyelids reopens. Testes begin to descend into the scrotal
pouch. Body length is 350 mm; CR is 270 mm, weight approximately 1200 g.
In the 8th lunar month the amount of subcutaneous fat increases, the fetus is plump,
pink with hair on its head; nails reach to the ends of fingertips. There is plenty of
vernix caseosa on the body surface. Body length is 400 mm; CR is 310 mm, the fetus
weights approximately 1800 g.
3
In the 9th lunar month changes which began in the 8th lunar month continue. Descend
of testes is finished. Body length is 450 mm, CR is 340 mm, and weight is
approximately 2600 g.
In 10th lunar month by this time a full-term baby is ready to be born: its body is
plump, skin is smooth without lanugos. Nails reach over the ends of finger tips, hair is
at least 10 mm long. Bones on the head are hard, cartilage is firm and fontanels are
palpable. Perimeter of the chest is slightly larger than perimeter of the head. Body
length is approximately 500 mm, CR length is approximately 360 mm, and average
weight is 3300 g. These signs are evaluated by a neonatologist right after the delivery
(53)
.
1-1-2 Pathophysiology:
The fetal and neonatal periods are ones of continuing development at both organ
and tissue level, first by a process of cell division and then by growth of individual
cells. There is rapid somatic growth, which is roughly linear for most of the second
and third trimesters, slowly down from about 38 weeks gestation until delivery (54).
Birth weight is affected by many different factors, both constitutional (e.g. genetic
factors, chromosomal abnormality) and environmental. The later may act directly on
the fetus (e.g. first trimester infection affect fetal cell mass), on the placenta (e.g.
haematogenous infection compromises fetomaternal transfer of oxygen and nutrients)
or via the mother (chronic under nutrition or poor utero placental perfusion from any
cause). Small women tend to have small babies as do women with some inherited
abnormalities such as Phenylketonuria (PKU). Babies from multiple gestations are of
lower birth weight than singletons. Low birth weight is a feature of many
4
malformation syndromes with major somatic defects such as dwarfism, anencephaly
and Meckel-Gruber syndrome (54).
Basically, there are three groups of birth weights that are important to the
clinicians; thus, the low birth weight, the normal birth weight, and the macrosomic
babies. Fetal growth restriction may be of early onset, when it is characteristically
symmetrical so that fetal organs are smaller but proportionally unchanged. Serial
measurements of BPD show that it grows below, but parallel to the centile lines. this
type of growth failure may be the result of intrauterine infection (TORCH), genetic
constitution, chromosome abnormality or malformation syndromes such as renal
agenesis. Late onset growth restriction results in asymmetric growth disturbance with
relative sparing of brain growth and therefore of head circumference and BPD. The
causes of this type of restrictions are usually environmental (reduced uteroplacental
perfusion in conditions such as pre-existing or pregnancy-associated hypertension,
maternal diabetes or non-availability of nutrients as seen in chronic maternal under
nutrition
(54)
. Some babies are inappropriately large for gestational age (large for
dates) these babies tend to be born taller, heavier women who are older and of higher
parity. Excessive maternal weight gain may be observed during pregnancy. Maternal
diabetes mellitus and gestational diabetes are associated with large babies.
Macrosomia is a feature of Wiedemann-Beckwith and Soto's syndromes
neonatal complications are more associated with low birth weight,
(11)
(54)
. Since
and labor
abnormalities as well as neonatal complications with fetal macrosomia,(12)accurate
estimation of fetal weight is of greater importance in taking management decisions as
regards delivery of these extremes of fetal weight.
5
Defining disorders of growth requires relating a given achieved growth to an
expected growth. In the case of fetal growth, three further levels of complexity arise.
First, growth is determined in part by gestational age and an apparent growth disorder
may reflect an inaccurate assessment of gestational age. Second, even if gestational
age is known accurately, the size of the fetus can only be assessed indirectly by
ultrasound. Third, even accepting these limitations, fetal measurements are typically
related to a population-based norm. Deviation from normal may arise from parental
determinants of growth, such as race and stature (55).
In last few decades, the estimation of fetal birth weight has advanced from
estimation by physical examination to fetal ultrasound using multiple parameters.
This has increased the accuracy of the fetal weight estimation significantly. Multiple
formulae have been developed for the estimation for birth weight using ultrasound
measurement. At present, fetal ultrasound is extensively used to estimate the fetal
weight (9). The birth weight is clinically classified as follows (13):
500
1,500 2,000 2,500 3,000
Birth weight less
1,000 –
–
–
–
–
–
(grams)
500
1,499
999
1,999 2,499 2,999 3,499
Very
Extremely
Low
Low Birth Normal
Classification Low Birth
Birth Weight
Weight
Weight
Weight
3,500 4,000 4,500 5,000
–
–
–
or
3,999 4,499 4,999 more
Birth
High Birth Weight
During the last decade, estimated fetal weight has been incorporated into the
standard routine antepartum evaluation of high-risk pregnancies and deliveries and
intra-partum evaluation and management of fetuses
(14, 15)
. High rate of perinatal
mortality is still a major cause for concern in developing countries16. Accurate EFW
6
would help in successful management of labor and care of newborn in neonatal period
and helps avoiding complications associated with fetal macrosomia or low birth
weight (LBW) babies, thereby reducing perinatal morbidity and mortality17.
Macrosomia is associated with risks to the mother as well like obstructed labor,
uterine rupture, cervical and vaginal lacerations, pelvic floor injuries and post-partum
hemorrhage. Thus EFW antenatally is of utmost importance to the obstetricians so
that:
• They can have preventive measures to deal with respiratory distress syndrome,
hypoglycemia in a LBW neonate
• Anticipate problems of shoulder dystocia in macrosomic fetus
• They can give perinatal counseling on likelihood of survival of the neonate
• Decide on the intervention to be undertaken to postpone preterm delivery, the
optimal route of delivery, or the level of hospital where delivery should occur.
Thus reduce the risk of mortality and morbidity to mother and neonate.
In utero growth of the fetus is assessed by fetal biometry, including
measurements of the head, abdomen and the femur. The results can be plotted on
separate charts to check whether the growth is within normal limits. Alternatively, the
measurements can be used to calculate and plot estimated fetal weight (EFW), which
is now considered to be a more appropriate method to monitor fetal growth during
pregnancy (56).
7
Diagram of BPD criteria
Diagram of FL criteria
8
Diagram for criteria of BPD ,AC and FL measurement
In fact, longitudinal ultrasound studies have shown that variation and the normal
range of fetal weight is constant throughout pregnancy, at about 10–11%, and that
growth continues until birth without any slowing (57, 58, 59).
The dynamics of growth in normal pregnancy can be studied by converting the
weight-for-gestation curve into a proportionality curve, where term weight in normal
pregnancies is equated to 100%.
Normal growth is not an average for the population, but one that defines the
optimal growth that a fetus can achieve, that is, the growth potential of each baby.
A number of studies have shown that standards for normal birth weight and growth
adjusted for constitutional variation are better than local population norms to separate
physiological and pathological smallness. Customized standards improve detection of
pathologically small babies (60, 61). Smallness defined by customized standards were
also more strongly associated with adverse pregnancy outcomes such as stillbirth,
neonatal death or low Apgar scores(62) and were more closely linked with a number of
pathological indicators such as abnormal antenatal Doppler, caesarean section for
fetal distress, admission to the neonatal unit and prolonged hospital stay(63).
9
Figure : Image of BPD thalamic veiw
Figure : image of HC this measured at the same level as the biparietal diameter, around the outer perimeter of the
calvarium. This measurement is not affected by head shape.
Figure : image of Abdominal circumference
10
Figure : image of Fetal Femur Length
The present study aims at assessing the fetal weight using shepherd's formula and
Hadlock’s formula, to do comparative evaluation of these methods and to know which
method almost correlates with the actual birth weight of the neonate at term.
11
1-2 Problem Statement
Knowledge of expected birth weight is important for obstetricians, as it is an
important variable affecting perinatal mortality
(7)
.
Fetal weight estimation is thought
to be helpful in managing the delivery of a large baby, where complications may
occur. The two most widely available means of estimating fetal weight is clinical
assessment and ultrasound estimation, have been shown to have roughly equivalent
accuracy, even in macrosomic fetuses, making it difficult to recommend one method
over the other based on hard evidence. Nonetheless, obtaining fetal weight estimation
by ultrasound provides some measures of objectivity over clinical estimation and has
been shown to be as accurate in obese women as in lean women.
Starting from the time of conception, this typical length of gestation and the fetal
age at the end of pregnancy is 266 days or 38 weeks (= conceptual age). In most (but
by no means all) cases conception occurs in mid cycle and thus 2 weeks are added to
denote menstrual age. By convention, gestational age is also expressed in this manner:
the formulae used for dating pregnancies by ultrasound, to determine the length of
pregnancy at any point and the expected date of delivery (EDD), also add a standard 2
weeks to derive ‘gestational age’. The typical length of pregnancy is 280 days or 40.0
weeks; term is conventionally denoted as 37–42 weeks, preterm as <37.0 weeks and
post-term >42.0 weeks(55).
The models that are commonly used for estimation of fetal weight are regression
models which are based on different combinations of sonographically measured fetal
biometric indices, mainly abdominal circumference (AC), femur length (FL),
biparietal diameter (BPD), and head circumference (HC). Some models include only
1 or 2 fetal indices, other models, in an effort to improve accuracy, incorporated either
12
3 or all 4 fetal indices. Nevertheless, it remains unclear which of the many models
available is the most accurate.
In some studies they compare the accuracy of 26 sonographic models for fetal weight
estimation using sonographic examinations performed up to 2 weeks before delivery
and to determine whether the accuracy of weight estimation improves with the
relationship to the number of fetal biometric indices in the model.
The common models are (7):
Group 1 AC
1
Campbell and Wilkin
2
Hadlock et al
3
Jordaan
4
Warsof et al
5
Higginbottom et al
Group 2 AC and FL
6
Hadlock et al
7
Woo et al
8
Warsof et al
Group 3 AC and BPD
9
Vintzileos et al
10
Warsof et al
11
Shephard et al
12
Jordaan
13
Hadlock et al
14
Woo et al
13
15
Hsieh et al
Group 4 AC and HC (±BPD)
16
Hadlock et al
17
Jordaan
18
Jordaan
Group 5 AC, FL, and BPD
19
Hadlock et al
20
Woo et al
21
Shinozuka et al
22
Hsieh et al
Group 6 AC, FL, and HC
23
Hadlock et al
24
Combs et al
25
Ott et al
Group 7 AC, FL, BPD, and HC
26
Hadlock et al
The two main ultrasonic methods used for predicting a macrosomic fetus are
based on measurement of fetal AC. It is currently unclear which of these two
ultrasound methods has better diagnostic accuracy in predicting macrosomia. A recent
systemic review aimed at evaluating the accuracy of biometry in prediction of
macrosomia demonstrated the following :( 7)
14

The most commonly used formulae for estimating fetal weight were Hadlock's
formula, using femur length and AC, and Shephard's formula, using biparietal
diameter and AC measurements;

The pooled positive likelihood ratio for an ultrasound EFW of more than 4000
g to predict an actual birth weight of more than 4000 g was 5.7 (4.3-7.6) by
Hadlock's formula (femur length/AC) with a respective negative likelihood
ratio of 0.48 (0.38-0.60);
The perinatal complications associated with low birth weight are most often
attributable to fetal prematurity, but may sometimes also arise as the result of
intrauterine growth restriction. For macrosomic fetuses, potential complications
associated with delivery include shoulder dystocia, brachial plexus injuries, bony
injuries, and intrapartum asphyxia, as well as maternal risks that include birth canal
injuries, pelvic floor injuries damage, and postpartum hemorrhage. The occurrence of
cephalopelvic disproportion is more prevalent with increasing fetal size and
contributes to an increased rate of both operative vaginal delivery and cesarean
delivery for macrosomic fetuses compared with fetuses of normal weight(9)
15
1-3 Justification
The range and use of ultrasound fetal measurements have gradually been
extended. Although antenatal care has focused more on the diagnosis of fetal growth
restriction, the delivery of macrosomic infants is associated with higher rates of
adverse outcomes for both mother and infant in comparison to the delivery of normal
weight infants. Increased risks to the large infant include shoulder dystocia, brachial
plexus injury, perinatal asphyxia, and neonatal death
(5)
.
Adverse maternal outcomes
include prolonged labour, genital tract trauma, postpartum haemorrhage, and a higher
rate of caesarean delivery (6). By measuring ultrasound images of a fetus, it is possible
to estimate the baby’s weight at birth. This study in one way or another will assess the
reliability of ultrasound measurement in pregnant women at 37 or more weeks.
Ultrasound measurements had a tendency to overestimate the weight of small babies
while underestimating the weight of both large babies and the babies of diabetic
mothers
(8)
. Estimates of fetal weight (EFW) in late pregnancy are relied on as
potentially useful variables for clinical decision making in obstetrics. Clinical EFW
based on abdominal examination, including symphysis-fundus height measurements
and gestational age, tend to be in a range from accurate to unreliable.
Ultrasonographic imaging is currently considered sufficiently accurate for objective
estimation of fetal weight and clinical applicability. It can serve to determine the
weight of the fetus within 10% of actual birth weight (BW) in as many as 75% of
estimates and within 5% in as many as 40%. Errors associated with EFW of small or
large fetuses may be harmful if clinical decisions based on such erroneous estimates
result in inappropriately premature delivery or lead to surgical delivery in an effort to
avert the potential hazards of delivering possible macrosomic infants vaginally.
16
1-4 Objectives
1-4-1General objective
To assess the accuracy of ultrasound estimation of fetal weight in normal
vaginal deliveries at Al muglad hospital
1-4-2 Specific objectives
-
To compare the accuracy of different sonographic models for fetal weight
estimation {Hadlock's formula (3paramters) and Shephard's formula (2
parameters) }
-
To compare between ultra-sonographic estimation of fetal weight and birth
weight after delivery
17
1-5 Literature review
Estimation of fetal weight is done ultrasonographically using abdominal
circumference
(AC)
alone
(Campbell
and
Wilkin),AC
and
biparietal
(49-51)
diameter(BPD)(Sheppard et al)AC ,BPD and femur length (Hadlock et al)
Determination of weight within 10% of actual birth weight is considered acceptable
accuracy (52).
Both low birth weight and excessive fetal weight at delivery are associated with an
increased risk of newborn complications during labor and the puerperium
(48)
. The
perinatal complications associated with low birth weight are attributable to either
preterm delivery or intrauterine growth restriction (IUGR), or both. For excessively
large fetuses, the potential complications associated with delivery include shoulder
dystocia, brachial plexus injuries, bony injuries, and intrapartum asphyxia. The
maternal risks associated with the delivery of an excessively large fetus include birth
canal and pelvic floor injuries, as well as postpartum hemorrhage (48).
The occurrence of cephalopelvic disproportion is more prevalent with increasing
fetal size and contributes to both an increased rate of operative vaginal delivery and
cesarean delivery for macrosomic fetuses compared with fetuses of normal weight.
Depending on many factors, the optimal range for birth weight is thought to be 30004000 grams (48).
Mean birth weight has been described as a function of gestational age. Several
studies subdivide such results into those that apply to women of different race, male
versus female fetuses, and primiparous versus multiparous gravidas. Standard fetal
18
growth curves are useful for estimating the range of expected fetal weight at any
particular gestational age. However, in order for the growth curves to be useful, all
such tables presuppose that the gestational age of the fetus is established properly.
Without adequate gestational dating, the standard fetal growth curves cannot be
interpreted successfully (48).
The principle limitations of standard fetal growth curves that are derived from
population-based studies are as follows (48):

They apply only to fetuses that are of normal size for gestational age and not
to those with significant (and potentially pathologic) growth abnormalities.

The standard deviation (SD) associated with the mean birth weight estimate at
any particular gestational age is wide, typically exceeding 450-500 grams.

The fetus's gestational age must be known with a high degree of certainty to
use the growth curves with any degree of reliability.
In general, these growth curves can expect to apply to large populations of
pregnant women who have well-dated pregnancies, but the limits of their predictive
accuracy make them less than ideal tools for estimating fetal weight for individual
patients. The range of birth weights at any particular gestational age spans a wide
array of values, with 95% confidence intervals of more than 1600 grams at term. In
addition, the fetal growth curves are the most inaccurate at the extremes of fetal
weight deviation (i.e., women carrying fetuses that are either growth restricted or
macrosomic).
19
All of the currently available methods for assessing fetal weight in utero are
subject to significant predictive errors. These errors are the most clinically relevant at
the 2 extremes of birth weight (e.g., those <2500 g who also are more likely the
products of premature deliveries, and those >4000 g who are at risk for the
complications associated with fetal macrosomia).
Tactile Assessment of Fetal Size: The oldest technique for assessing fetal weight
involves the manual assessment of fetal size by the obstetrician. Worldwide, this
method is used extensively because it is both convenient and costless; however, it has
long been known as a subjective method that possesses large predictive errors.
Clinical Risk Factor Assessment: Quantitative assessment of clinical risk factors
has previously been shown to be valuable in predicting deviations in fetal weight.
Maternal Self-Estimation: A third method for estimating fetal weight is via
maternal self-estimation. Perhaps surprisingly, these maternal self-estimations of fetal
weight in multiparous women show comparable accuracy in some studies to clinical
palpation for predicting abnormally large fetuses.
Sonographic prediction algorithms: used to make fetal weight estimations in these
various studies were those of Shepard, Hadlock, Sabbagha and Warsof, in addition to
the best of 8 algorithms based upon various combinations of AC, FL, BPD, and HC,
both singly and in combination.
Obstetric sonographic assessment for the purpose of obtaining fetal biometric
measurements to predict fetal weight has been integrated into the mainstream of
obstetric practice during the past quarter century. From its inception, this method has
20
been presumed to be more accurate than clinical methods for estimating fetal weight.
The reasons for this assumption are varied, but the fundamental underlying
presumption is that the sonographic measurements of multiple linear and planar
dimensions of the fetus provide sufficient parametric information to allow for
accurate algorithmic reconstruction of the 3-dimensional fetal volume of varying
tissue density. Consistent with these beliefs, much effort has generated best-fit fetal
biometric algorithms that can make birth weight predictions based on obstetric
Ultrasonographic measurements. As such, the Ultrasonographic technique represents
the newest and most technologically sophisticated method of obtaining birth weight
estimations.
In-utero fetal biometric assessment made by obstetric Ultrasonography use bestfit algorithms to make birth weight predictions
(18)
. This provides an attractive
‘objective’ method of estimating birth weight. Willocks and colleagues(19) were
among the first to report their experience with ultrasound fetal weight estimation, and
commented that clinical estimation of fetal weight is little more than guess work
because of the influence of factors such as abdominal wall thickness, uterine tension,
volume of amniotic fluid, and position of the fetus in utero. It was claimed that in two
thirds of cases fetal weight could be estimated to within about one pound using
ultrasound. A large number of fetal weight prediction formulae have since been
suggested based on fetal biometry including head biparietal diameter (BPD), head
circumference (HC), femur length (FL) and abdominal measurements. A study was
done by Shamley and Landon (20) to evaluate prospectively four published equations
by Shepard et al,(21) Hadlock et al,(22). Rose and McCallum, (23) and Sabbagha et al,(24)
as well as clinical estimation for accuracy in determining fetal weight in labour.
21
The equations are known to use the following parameters:
a) Hadlock et al
-FL and abdominal circumference (AC)
b) Shephard et al - BPD and AC
c) Rose and McCallum - FL and abdominal diameter
d) Sabbagha et al – a set of equations that use gestational age to account for fetal size,
dividing the fetuses into three groups according to AC:
SGA (small for gestational age) AGA (appropriate for gestational age) or LGA (large
for gestational age)
The Hadlock and Shepard equations both had a lower percentage of error than the
Sabbagha formula (6.1% and 6.2% respectively, versus 7.8%; P<0.007). For all four
equations, 70-79% of fetal weight predictions were within 10% of actual birth weight.
The Shepard formula, however, has limited application in labour because head
descent obscures the biparietal diameter which is essential to the fetal weight
calculation. The conclusion from this study was that using any of the four standard
equations or clinical examination, accurate estimation of fetal weight could be
achieved for patients in labour, even in the presence of ruptured membranes. The
accuracy of these ultrasound estimations presented here was not found in a number of
other studies comparing simple palpation estimates with ultrasound based predictions.
In these comparisons, the percentage of predictions within 10% of the birth weight for
ultrasound estimation ranged from 39% to 69 %.(25-29,
30-32)
.
While ultrasound fetal
weight estimation may not appear significantly better than clinical methods, a recent
22
comparison by Peregrine et al has shown that estimation by ultrasound immediately
before labor was more accurate than clinical estimation for low and high birth weight
babies, where clinical estimates are known to be relatively inaccurate (33).
A study by Yoni et al
(34)
looked at the effect of oligohydramnios on intrapartum
estimation of fetal weight. The conclusion was that in term patients, intrapartum
sonographic prediction of birth weight in the presence of reduced amniotic fluid
volume offered no advantage over estimated fetal weight obtained by abdominal
palpation. However, the presence of oligohydramnios significantly reduced the
accuracy of intrapartum clinical as well as sonographic fetal weight estimations.
Therefore it was suggested that intrapartum fetal weight estimation be obtained prior
to artificial rupture of membranes. Since the Hadlock equation does not rely on BPD
measurements, it appears to be both the most accurate and clinically useful method for
predicting fetal weight for patients in labour at term. Although the validity and
reproducibility of these formulas has been documented in clinical practice with a
reported systematic error of 10% or less relative to the actual birth weight, it is well
recognized that various fetal factors may influence the accuracy of fetal weight
estimations. However, there are few reports that document the effect of certain
maternal characteristics, specifically maternal size and obesity, on the ability to obtain
Ultrasonographic fetal biometric measurements and consequently calculate reliable
fetal weights.
Newer technologies may be able to provide better fetal weight estimation. Threedimensional (3-D) sonography potentially allows superior fetal weight estimation by
23
including soft tissue volume of the fetal thigh, upper arm and abdomen.35.36 .
While several studies assume that a lower BW has a negative impact on the
accuracy of FWE, seven studies specifically investigated this hypothesis (37, 38, 39).
Three studies found that there is an effect (37, 40 and 39). Melamed et al. (37) reported that
random error in particular increases with decreasing BW unrelated to the formula
used. Meyer et al.41 on the other hand did not report an effect in their study of 664
neonates. They divided their population into ten different weight groups, including a
total of 157 neonates with a BW <1,500 g. Even though they found a significant
tendency to underestimate fetal weight in all tested formulas, this finding was
unrelated to BW as there was no significant difference in random or systematic error
in all BW groups. Heer et al. (38) who did not find an effect either divided their study
population into 2 groups: BW >2,000 g versus BW <2,000 g. This rather rough
distinction might be the reason for their findings, as they did not pay special attention
to the extremes of BW. One study (42) found that depending on the formula used for
FWE, different results are obtained. For FWE with the Scott formula, a significant
overestimation was found in VLBW neonates, whereas FWE with the Had-lock I
formula seems to correlate well with the actual BW (42).
Seventeen studies tried to evaluate the best formula for FWE
(37, 38, 43, 42, 44-47)
. The
most frequently examined formulas are those of Hadlock, which were compared to
other formulas , except
in the study by Mills et al.(43)who only compared two
formulas (Shepard and Warsof). The formulas of Camp-bell, Merz, Shepard and
Warsof have been examined 7, 8, 12 and 8 times, respectively. Thirteen of the studies
found one of the Hadlock formulas to be the most accurate
24
(37, 38, 42-45)
. All Hadlock
formulas seem to be equally accurate, as Meyer et al.(41) who compared five Hadlock
formulas found no significant difference in systematic or random error.
25
Chapter 2: Research Methods
26
2- Methodology
2-1 Study design:
Cross Sectional Study
2-2 Study area:
The study area was Al-muglad hospital. It 80 beds and ultrasound department
with 2 machines, labour room and an obstetrician and it serves about 130,000 people
according to 2008 census (population of the study area). Al muglad hospital is a
relatively new hospital constructed in 1990 to serve the nomadic people of Abyie
locality along with the people of surrounding localities and states. This hospital
provide curative and preventive services which is being promoted day by day since its
foundation, these services include internal medicine, obstetrics and gynecology,
pediatrics, surgery and some minority specialties. The hospital also provides
diagnostic x-ray and ultrasound.
The monthly mean of patients attending the hospital is approximately more than
4000. There is one obstetrician and one diagnostic ultrasound specialists in ultrasound
department. The department has 2 ultrasound machines. Study was done with
Mindary DP10 machine probe 2.5 – 5 MHz frequencies.
26
2-3 Study population: (Inclusion exclusion criteria)
All the patients were adequately counseled and their written consents obtained
before recruitment into the study.
The data of pregnant term ladies will be searched for all sonographic fetal weight
estimations performed within 1 week before delivery between Jan - Apr 2015 at Al
muglad hospital according to sampling and inclusion/exclusion criteria.
2-3-1 Inclusion: Sudanese residence in Al muglad area, singleton pregnant ladies,
gestational age term pregnant ladies.
2-3-2 Exclusion: women were in active labor or with ruptured membranes, eclampsia
patients, diabetics, previous cesarean section cases in which not all 4 biometric
indices were recorded, twin pregnancy, congenital malformations and hydrops fetalis.
74 antenatal women between 36and 42 weeks gestation
• The patients were selected from outpatient department and maternity wards who had
their last fetal weight estimation done within 1 week of delivery.
2-4 Sampling: (Type, size, frame, technique)
Systematic random sample, sample size will be calculated according to the equation
n= Z 2 * (p) * (1-p)/ d 2
Where:
•
Z = Z value (e.g. 1.96 for 95% confidence level)
p = prevalence or % of disease
(.5 used for sample size needed)
d = confidence interval, expressed as decimal
n = (1.96)2 *0.5*0.5/(0.05)2 = 74
27
2-5 Data collection
A cross sectional study was used. All pregnant ladies during study period were
included after adequate counseling and written consent for participation in the study,
according to inclusion/exclusion criteria.
Data of personal information and clinical history was collected from patient’s files of
peri-natal follow up and admission sheets. Data of sonographic examination was
collected from patients by carrying out obstetric scans on each participant, in a supine
comfortable position after informed consent. Sonographic evaluations include the
standard fetal biometric measurements (abdominal circumference (AC), femoral
length (FL), biparietal diameter (BPD), and head circumference (HC). the relevant
head image required for the measurement of the biparietal diameter (BPD), occipitofrontal diameter (OFD) and head circumference (HC) is a transverse axial plane,
which includes the falx cerebri anteriorly and posteriorly, cavum septum pellucidum
anteriorly in the midline, and the thalami. The BPD should measured at the widest
point of the head from the outer edge of the nearest parietal bone to the inner edge of
the more distant parietal bone and the OFD perpendicular to the BPD from mid to mid
occipital bones.
The head circumference traced either with an ellipse mode or
manually around the outer perimeter of the skull. In late pregnancy it can be difficult
to obtain the ideal imaging plane due to the head lying low in the pelvis.
The imaging plane for the abdominal circumference (AC) is a true transverse
cut at the level of the fetal liver and stomach, including the left portal vein at the
umbilical region. Although the AC can be measured using the ellipse mode, in the
third trimester it is usually more precise to manually trace the perimeter of the
abdomen, including the fat layer. Long bones imaged in the axial plane to achieve the
28
longest length, with clean blunt ends and a strong acoustic shadow behind the bone.
Measuring must be along the diaphyseal shaft, excluding the epiphysis.
Diagrammatic scheme for sonographic criteria of BPD, AC and FL measurements
Antenatal data, Patient age (years), Parity, Gravidity, Significant medical diseases
gestational diabetes mellitus (GDM), Fibroid, Abnormal liquor volume), Mode of
delivery (Vaginal delivery, Vacuum extraction, Caesarean delivery) Time of scan to
delivery (days) gestational age at delivery, and actual birth weights (BWs) of each
participant’s neonate will be measured within 30 min after delivery, by trained
assistants (midwives) using a standardized neonatal weighing scale.
Fetal weight estimations compared with the actual BW, and the following measures of
accuracy were calculated for each model: (1) correlation with the actual birth weight
(2) systematic error which reflects the systematic deviation of a model from the actual
birth weight, expressed as the percentage of the actual birth weight; (3) random error,
a measure of precision (rather than accuracy) that reflects the random (or
nonsystematic) component of the prediction error;
2-6 Data analysis:
Data analysis was performed with the SPSS version 15.
29
2-7 Ethical concern:

The mothers were instructed about the purpose of the study and their right to
withdraw at any time.

Informed consent for participation was obtained before enrollment.

Approval for the study was obtained from the research ethical committee of
the University and ministry of health.
30
Chapter 3: Results & Discussion
31
3-1 Results:
The study included 74 patients. The gestational age was between 36 weeks and
40 weeks, with the mean GA at estimation 37.72 ± 0.99(36-40.57) and at birth 38.32
± 0.76(36.71-40.71). The age range of patients was between 15-41 years, with a mean
of 26.32 ± 6.28 years. The range of actual birth weight was between (2.6-4.4) kg with
a mean of 3314.05 ± 311.29 grams.
In (table 1 & figure 1) 13.5% of study women were in the age category 15-19
years. 45.9% in the age group 20-29 years, 37.8% in the age group of 30-39 years,
and 2.7% were of age group greater than or equal 40 years. 51.4% of patients live in
Almuglad, 12.2% lives in Eldibab, 10.8% are lives in Almairam, and 10.8% are lives
in Altoboon as shown in (table 2 &figure2). In (table 3&figure 3) sample distribution
by gravidity, most of the sample members are gravida 4 about 24.3% of women.
Whereas in sample distribution by parity (table 4), most of the sample members are
para 3 , 21.6% of women's, 13.5% para 0, 14.9% para 1, and 17.6% para 2.
In (table 5 &figure 5) GA at birth, 60.8% of women were in the gestation age
of 38-39 weeks, 21.6% of women were in the gestational age 37-38 weeks, 10.8% of
women were in the gestational age 39-40 weeks, 5.4% of women were in the
gestational age is greater than or equal 40 weeks, and other 1.4% of women were in
the gestational age between 36 and 37 weeks. 94.6% of newborns have a normal fetal
birth weight, as shown in (table 6 & figure 6).
The mean age of study patients was 26.32 years with the corresponding standard
deviation (SD) of 6.28 years, ranged from 15 to 41 years. The mean gravidity of study
patients was 4.27 times (approximately 4 time’s gravidity) with the corresponding
31
standard deviation (SD) of 2.12 times, ranged from 1 to 10 times. The mean parity of
study patients was 2.84 times (approximately 3 time’s parity) with the standard
deviation (SD) of 2.05 times, ranged from 0 to 9 times, (table7).
From (Figure 7) GA by different methods, the estimated mean gestational age of
study patients was 37.72 weeks with the corresponding standard deviation (SD) of
0.99 weak, ranged from 36 to 40.57 weeks. The birth mean gestational age of study
patients was 38.32 weeks with the corresponding standard deviation (SD) of 0.76
weeks, ranged from 36.71 to 40.71 weeks. From standard deviation the values of at
estimated are more scattered from at birth from the mean.
The mean estimated fetal weight by Hadlock was 3269.53 grams with the
corresponding standard deviation (SD) of 312.58 grams, ranged from 2691 to 4223
grams. The mean estimated fetal weight by shephards of the study was 3304.41 grams
with the corresponding standard deviation (SD) of 332.41 grams, ranged from 2567 to
4247 grams. The mean actual fetal weight of the study was 3314.05 grams with the
corresponding standard deviation (SD) of 311.29 grams, ranged from 2600 to 4400
grams, also from standard deviation the estimated by Hadlock is centralized to the
mean more than estimated by Shephard's, (figure 8) Estimation of fetal weight by
different methods.
3-1-1 Statistical analysis:
To determine the personal data, frequencies, percentages and means (where
appropriate) were computed. Percentages, means and standard deviations were first
computed. ANOVA table were used to compare between more than or equal three
groups. Independent sample t test were used to compare between two groups in the
32
mean. Kruskal Wallis Test was used for three or more groups in the mean this test
considered non parametric test. Pearson’s correlation coefficient within 95%
confidence interval p values <0.05 were considered as statistically significant. The
results were considered statistically significant when the p-value was calculated less
than 0.05 at a confidence interval of 95%.
33
Table (1) Sample distribution by age group:
Frequency
Percent
15-19 years
10
13.5%
20-29 years
34
45.9%
30-39 years
28
37.8%
40 years and more
2
2.7%
Total
74
100%
Age group
45.9%
50.0%
37.8%
40.0%
30.0%
20.0%
Percent
13.5%
2.7%
10.0%
0.0%
15-19 years
20-29 years
30-39 years
Figure (1) Sample distribution by age group:
34
40 years and
more
Table (2) Sample distribution by residence:
Frequency
Percent
Abulikri
Adila
Almairam
Almgdama
Almuglad
Alsitaib
1
1
8
5
38
1
1.4%
1.4%
10.8%
6.8%
51.4%
1.4%
Altoboon
Eldibab
Kigeera
8
9
2
10.8%
12.2%
2.7%
Sharif
1
1.4%
Total
74
100%
Residence
60.0%
51.4%
50.0%
40.0%
30.0%
20.0%
10.0%
10.8%
1.4%
Percent
10.8% 12.2%
6.8%
1.4%
1.4%
0.0%
Figure (2) Sample distribution by residence:
35
2.7%
1.4%
Table (3) Sample distribution by gravidity:
Frequency
Percent
1
2
3
4
5
5
11
13
18
7
6.8%
14.9%
17.6%
24.3%
9.5%
6
7
8
8
4
6
10.8%
5.4%
8.1%
9
10
1
1
1.4%
1.4%
Total
74
100%
Gravidity
24.3%
25.0%
20.0%
17.6%
14.9%
15.0%
9.5%
10.0%
10.8%
Percent
8.1%
6.8%
5.4%
5.0%
1.4%
1.4%
0.0%
1
2
3
4
5
6
Figure (3) Sample distribution by gravidity:
36
7
8
9
10
Table (4) Sample distribution by parity:
Frequency
Percent
0
1
2
3
4
5
6
10
11
13
16
10
6
4
13.5%
14.9%
17.6%
21.6%
13.5%
8.1%
5.4%
7
8
9
2
1
1
2.7%
1.4%
1.4%
Total
74
100%
Parity
25.0%
21.6%
20.0%
15.0%
17.6%
13.5%
14.9%
13.5%
Percent
8.1%
10.0%
5.4%
2.7%
5.0%
1.4%
1.4%
0.0%
0
1
2
3
4
Figure (4) Sample distribution by parity:
37
5
6
7
8
9
Table (5) Sample distribution by GA (at birth):
Frequency
Percent
36-37
37-38
38-39
39-40
40-
1
16
45
8
4
1.4%
21.6%
60.8%
10.8%
5.4%
Total
74
100%
GA(At birth)
70.0%
60.8%
60.0%
50.0%
40.0%
Percent
21.6%
30.0%
20.0%
10.0%
10.8%
5.4%
1.4%
0.0%
36-37
37-38
38-39
Figure (5) Sample distribution by GA (at birth):
38
39-40
40-
Table (6) Sample distribution by Actual fetal weight:
Frequency
Percent
Normal
abnormal
70
4
94.6%
5.4%
Total
74
100%
Actual fetal weight
5.4%
Normal
Upnormal
94.6%
Figure (6) Sample distribution by Actual fetal weight:
39
Table (7) shows the minimum, maximum, mean, and standard deviation:
Mean ± SD(range)
Age in yrs
Gravidity
Parity
GA At Estimated
GA At Birth
EFW (in grams) by Hadlock
26.32 ± 6.28(15-41)
4.27 ± 2.12(1-10)
2.84 ± 2.05(0-9)
EFW (in grams) by shephards
AFW (in grams)
3304.41 ± 332.41(2567-4247)
3314.05 ± 311.29(2600-4400)
37.72 ± 0.99(36-40.57)
38.32 ± 0.76(36.71-40.71)
3269.53 ± 312.58(2691-4223)
39.50
GA in weaks
39.00
38.50
0.76
SD
0.99
Mean
38.00
37.50
38.32
37.72
37.00
Estimated
Birth
GA method
Figure (7) Gestational age by different methods
40
3700.00
Weight in grams
3600.00
3500.00
332.41
312.58
311.29
3400.00
SD
3300.00
3200.00
Mean
3304.41
3269.53
3314.05
3100.00
3000.00
Estimated by hadlock
Estimated by
shephards
EFW method
Figure (8) Estimation of fetal weight by different methods
41
Actual
3-1-2 Comparison of expected fetal weight by different methods:
Table (8) ANOVA table for comparison between means by different methods:
Sum of Squares
Df
Mean Square
F
p-value
Between Groups
81208.93
2
40604.46
0.40
0.67
Within Groups
22272342.07
219
101700.19
Total
22353551.00
221
The obtained F value was 0.40 with the corresponding P = 0.67 as the obtained P >
0.05 it means that there is no significant difference in the actual, Hadlock and
shephards weight calculated by the two methods.
Table (9) multiple comparisons (post-hoc analysis)
(I) factor
(J) factor
Mean Difference
(I-J)
P-value
EFW by Hadlock
EFW by shephards
AFW (in grams)
-34.878
-44.527
0.507
0.397
EFW by shephards
EFW by Hadlock
AFW (in grams)
34.878
-9.649
0.507
0.854
AFW (in grams)
EFW by Hadlock
EFW by shephards
44.527
9.649
0.397
0.854
However, there is higher difference in average EFW by Hadlock methods
(44.527 grams) by comparing it with actual fetal weight through post hoc analysis that
is; Hadlock method on an average predicted 44.527 grams more than that of actual
fetal weight and P value is non-significance. The difference in prediction between
shephards and actual fetal weight on average was 9.649 grams that is shephards
methods on average predicted 9.649 grams higher weight than actual fetal weight but
P value was non-significant.
42
Table (10) Difference between actual fetal weight (in grams) versus Hadlock and
shephards method descriptive statistics:
N
Mean difference (average)
SD
Estimated by Hadlock
74
44.527
133.79613
Estimated by shephards
74
9.6486
214.05296
SD: standard deviation, N: number of cases.
average mean difference of EFW
300.00
200.00
100.00
133.80
214.05
44.53
9.65
Std. Deviation
Mean
0.00
Estimated by
hadlock
Estimated by
shephards
Figure (9) Average mean difference of estimation of fetal weight
The mean difference was greater for Hadlock methods (44.527 grams) than
shephards (9.6486 g). The standard deviation on Hadlock is less than standard
deviation on shephards that means the Hadlock method is fewer scattered compared
with shephards method.
43
Table (11) independent sample T test:
t
df
P-value
EFW by Hadlock – EFW by shephards
-0.658
146
0.512 (NS)
EFW by Hadlock – AFW
-0.868
146
0.387 (NS)
EFW by shephards – AFW
-0.182
146
0.856 (NS)
-4.135
146
0.000 (S)
Fetal weight
Gestational age
GA(at estimated) – GA(at birth)
P-value is less than 0.05 than mean significant different between both methods (reject
the null hypothesis), df ≡ degree of freedom, S≡ significant statistically, NS≡ non
significant statistically.
Null hypothesis: there is no significant different between method A and method B.
Alternative hypothesis: there is significant different between method A and method B.
From above table there are no significant different between means for EFW by
Hadlock and EFW by shephards (P-value = 0.512 is greater than 0.05), there is no
significant different between means for EFW by Hadlock and actual fetal weight (Pvalue = 0.387 is greater than 0.05), and there is no significant different between
means for EFW by shephards and actual fetal weight (P-value = 0.856 is greater than
0.05).
There are significant different between gestational age at estimated and gestational
age at birth (P-value = 0.000 is less than 0.05).
44
Table (12) Paired sample correlation:
Correlation
P-value
EFW by Hadlock – EFW by shephards
0.901
0.000(S)
EFW by Hadlock – AFW
0.908
0.000(S)
EFW by shephards – AFW
0.781
0.000(S)
P-value is less than 0.05 than mean significant correlation between both methods, S≡
significant statistically correlation.
The correlation is significant for all fetal weights, but the correlation between
estimated fetal weight by Hadlock and actual fetal weight is greater than the
correlation between estimated fetal weight by shephards and actual fetal weight that
means the estimated fetal weight by Hadlock is better than estimated fetal weight by
shephards.
Figure (10) Scatter plot Correlation between Estimated fetal weight by Hadlock and
actual fetal weight:
The scatter plot between actual fetal weight and estimated fetal weight by
Hadlock equation shows positive correlation while r value indicates that it is of high
correlation (r2 = 0.825).
45
Figure (11) Scatter plot Correlation between Estimated fetal weight by shephards and
actual fetal weight:
The scatter plot between actual fetal weight and estimated fetal weight by
shephards equation shows positive correlation while r value indicates that it is of high
correlation (r2 = 0.61).
46
Figure (12) Scatter plot Correlation between Estimated fetal weight by shephards and
actual fetal weight:
The scatter plot between estimated fetal weight by Hadlock and estimated fetal
weight by shephards equation shows positive correlation while r value indicates that it
is of high correlation (r2 = 0.811).
Table (13) Means for fetal weight by age group:
Age group
Estimated fetal weight
(in grams) by Hadlock
15-19 years
20-24 years
3313.4
3142.4
Estimated fetal weight
(in grams) by
shephards
3393.8
3180.4
25-29 years
30-34 years
35-39 years
3283.9
3359.9
3278.2
3264.21
3406.64
3302.83
3335.71
3406.36
3266.67
3201
3259
3200
3269.5
3304.41
3314.05
40 years and more
Total
Actual fetal weight
(in grams)
3370
3195
Table (14) Kruskal Wallis Test by age group:
EFW by Hadlock (in grams)
EFW by shephards(in grams)
AFW (in grams)
47
Chi-Square
df
p-value
5.92
4.976
5.94
5
5
5
0.314
0.419
0.312
Null hypotheses: there is no significant different between age group in the mean of
(EFW by Hadlock, EFW by shephards, AFW).
Alternative hypotheses: there is significant different between age group in the mean of
(EFW by Hadlock, EFW by shephards, AFW).
All p-values (0.314, 0.419, 0.312) for EFW by Hadlock, EFW by shephards, actual
weight respectively is greater than 0.05 significant level that mean there are no
significant different between means of weight by age group.
Table (15) Means for fetal weight by residence:
Residence
Abulikri
Adila
Estimated fetal weight
(in grams) by Hadlock
3361
3096
Estimated fetal weight
(in grams) by shephards
3098
3357
Actual fetal weight (in
grams)
3300
3200
Almairam
3325.9
3320.38
3400
Almgdama
3274.2
3238.4
3340
Almuglad
3235.6
3281.34
3285.26
3230
3341
3000
3363.8
3177.8
3432.5
3205.78
3412.5
3166.67
Kigeera
3783
3917.5
3950
Sharif
3253
3137
3300
Total
3269.5
3304.41
3314.05
Alsitaib
Altoboon
Eldibab
48
Table (16) Kruskal Wallis Test by residence:
Chi-Square
df
Estimated fetal weight (in grams) by Hadlock
4.506
9
Asymp.
Sig.
0.875
Estimated fetal weight (in grams) by shephards
7.484
9
0.587
Actual fetal weight (in grams)
9.771
9
0.369
Null hypotheses: there is no significant different between residence group in the mean
of (EFW by Hadlock, EFW by shephards, AFW).
Alternative hypotheses: there is significant different between residence group in the
mean of (EFW by Hadlock, EFW by shephards, AFW).
All p-values (0.875, 0.587, 0.369) for EFW by Hadlock, EFW by shephards, actual
weight respectively is greater than 0.05 significant level that mean there are no
significant different between means of weight by residence group.
Average predictive error per g body weight was less by Shephard’s
9.649 g as
compared to that by Hadlock’s method 44.527 g. between 2600 and 4400 gram
estimation was almost correlating with the actual birth weight. EFW of the birth
weight between 2691 and 4223 gram by Hadlock’s formula with mean 3269.53. Birth
weight between 2567 and 4247 gram by Shephard’s formula with mean 3304.05. The
mean difference was for Hadlock’s method and actual fetal weight is (44.527 g) more
than for Shephard’s method and actual fetal weight is (9.649 g). The mean difference
was for Hadlock’s method and Shephard’s method is (34.878 g). The obtained F
value was 0.40 with the corresponding P = 0.67. As the obtained P > 0.05 it means
that there is no significant difference in the birth weight calculated by the two
methods.
49
The correlation is significant for all fetal weights, but the correlation between
estimated fetal weight by Hadlock and actual fetal weight (0.908) is greater than the
correlation between estimated fetal weight by shephards and actual fetal weight
(0.781) that means the estimated fetal weight by Hadlock is better than estimated fetal
weight by shephards. Also the correlation is significant between estimated fetal
weight by Hadlock and estimated fetal weight by Shephard's (0.901).
50
3-2
Discussion:
This study was conducted to compare the accuracy of sonographic models for
fetal weight estimation (Hadlock's and Shepard's formulas) and to compare all with
the actual fetal weight after delivery. The accuracy of fetal weight is important in
obstetrical practice, as many decision depends on this .e.g. in macrosomia decision
will be different and in low birth weight management will be totally different.
Multiple studies are conducted and many regression models are made and multiple
formulas have been tried but still fetal weight estimation is not accurate and weight
predicted by ultrasound differs from actual fetal weight as stated in our literature
review. The ultrasound estimation of fetal weight in term pregnancies is used to
determine growth, and this may affect the timing and route of delivery.
3-2-1 Age group distribution, Gravidity and parity:
Birth weight is a key variable affecting fetal and neonatal morbidity,
particularly in preterm and small-for-dates babies. In addition, it is of value in the
management of breech presentations, diabetes mellitus, trial of labour, macrosomic
fetuses and multiple births. The mean age of pregnant women in the present study
was 26.32 years (Table1&7 figures 1&7). The minimum age of mothers in the present
study was 15, and maximum was 41years. There was no statistically significant
increase in birth weight with age, as shown in (table 13& 14), p-values (0.314, 0.419,
0.312) for EFW by Hadlock, shephards and actual fetal weight respectively This
finding is not in line with other studies Heer IM, Kumper C(38, 48). The mean gravidity
(table 3 &figure3) and parity (table 4 &figure4) is 4 & 3 respectively, which resemble
other studies (13-22).
51
3-2-2 GA distribution and estimated fetal weight by Hadlock and shephards and
actual fetal weight:
Accurate sonographic EFW can be an intangible objective for any sonographer
because at the endpoint ultrasound estimated fetal weight will lead to a management
decision that will have a direct impact on the mother and fetus. The mean estimated
fetal weight (in grams) by Hadlock formula seems to correlate well with actual fetal
weight after delivery, mean of Hadlock was 3269.53 ± 312.58(2691-4223) with the
corresponding standard deviation (SD) of 312.58 grams, ranged from 2691 to 4223
grams, and by shephards was 3304.41 ± 332.41(2567-4247), with the corresponding
standard deviation (SD) of 332.41 grams, ranged from 2567 to 4247 grams as shown
by (table 7and figures 7 &8). Whereas actual birth weight was 3314.05 ± 311.29
(2600 - 4400), with the corresponding standard deviation (SD) of 311.29 grams
ranged, from 2600 to 4400 grams. Average predictive error per g body weight was
less by Shephard’s
9.649 g as compared to that by Hadlock’s method 44.527 g.
between 2600 and 4400 gram estimation was almost correlating with the actual birth
weight. EFW of the birth weight between 2691 and 4223 gram by Hadlock’s formula
with mean 3269.53. Birth weight between 2567 and 4247 gram by Shephard’s
formula with mean 3304.05. The mean difference was for Hadlock’s method and
actual fetal weight is (44.527 g) more than for Shephard’s method and actual fetal
weight is (9.649 g). The mean difference was for Hadlock’s method and Shephard’s
method is (34.878 g). The obtained F value was 0.40 with the corresponding P = 0.67.
As the obtained P > 0.05 it means that there is no significant difference in the birth
weight calculated by the two methods. These findings agree with the results of studies
52
done previously like Shamley and Landon
(20)
, Shephard et al,(21) Hadlock et al,(22).
Rose and McCallum,(23) and Sabbagha et al,(24).
3-2-3 Correlation between Estimated fetal weight by Hadlock, shephards and
actual fetal weight:
The correlation is significant for all fetal weights estimations, but the
correlation between estimated fetal weight by Hadlock and actual fetal weight (0.908)
is greater than the correlation between estimated fetal weight by shephards and actual
fetal weight (0.781) that means the estimated fetal weight by Hadlock is better than
estimated fetal weight by shephards. Also the correlation is significant between
estimated fetal weight by Hadlock and estimated fetal weight by Shephard's (0.901).
The correlation is significant for all fetal weights estimations, but the correlation
between estimated fetal weight by Hadlock and actual fetal weight is greater than the
correlation between estimated fetal weight by shephards and actual fetal weight that
means the estimated fetal weight by Hadlock is better than estimated fetal weight by
shephards. From standard deviation the estimated by Hadlock is centralized to the
mean more than estimated by Shephard's. These results are in line with the
studies which found one of the Hadlock formulas to be the most accurate
thirteen
(37, 38, 42-45)
.
Hadlock formulas seem to be equally accurate, as Meyer et al.(41) who compared five
Hadlock formulas found no significant difference in systematic or random error.
53
Chapter 4: Conclusions & recommendations
54
4-1
Conclusion:
In conclusion, fetal weight estimation is important to diagnose perinatal
complication and in the management of labour and delivery, since birth weight affects
fetal and neonatal morbidity, particularly in preterm and small-for-dates babies. In
addition, it is of value in the management of breech presentations, diabetes mellitus,
trial of labour, macrosomic fetuses and multiple births. The study stated that the mean
age of pregnant women in the present study was 26.32 years with minimum of 15
years, and maximum of 41years with no statistically significant increase in birth
weight with advancing age. The mean gravidity and parity is 4 & 3 respectively.
Further more our study showed that the mean estimated fetal weight by Hadlock
formula seems to correlate well with actual fetal weight after delivery, mean of
Hadlock was 3269.53 ± 312.58(2691-4223) with the corresponding standard deviation
(SD) of 312.58 grams, ranged from 2691 to 4223 grams, and by shephards was
3304.41 ± 332.41(2567-4247), with the corresponding standard deviation (SD) of
332.41 grams, ranged from 2567 to 4247 grams. Whereas actual birth weight was
3314.05 ± 311.29(2600-4400), with the corresponding standard deviation (SD) of
311.29 grams, ranged from 2600 to 4400 grams. estimation of fetal weight by
Hadlock has been more correlated with actual fetal weight (AFW) than that done with
shephards formula, although the correlation was significant for all fetal weights
estimations by the two formulas , but the correlation of estimated fetal weight by
Hadlock and actual fetal weight is greater than the correlation of estimated fetal
weight by shephards and actual fetal weight which means that the estimated fetal
weight by Hadlock is better than estimated fetal weight by shephards. So using
Hadlock formula is more accurate in estimation of fetal weight by sonography.
54
4-2 Recommendations:
Based on the findings from this study, Hadlock formula (3 parameters) is more
accurate than shephards formula (2 parameters) in fetal weight estimation using
sonography. More studies is advised to be done because our research was the first to
be done in that area, so further researches is needed to compare clinical and maternal
estimation of fetal weight assessment in late pregnancy. WHO and MOH efforts is
required to brought sophisticated sonar machines in order to facilitate sonographic
estimation of fetal weight and promote sonography duties in general.
55
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in SGA births defined by customized versus population-based birthweight
standards. Br JObstet Gynaecol 108, 830–4.
63 - McCowan L, Harding JE & Stewart AW (2005) Customised birthweight
centiles predict SGA pregnancies with perinatal morbidity. Br JObstet
Gynaecol 112, 1026–33.
64
Patie
nt
NO.
date
Age
residence
Of
Mot
hers
gravi
dity
pari LM
ty
P
Actu
al
date
of
deliv
ery
EDD
In
yrs
By
By
LMP
U/S
Estimated
fetal weight
(in grams)
GA
by
At
estim
At
birth
hadl
ock
sheph
ards
Actual
fetal
weigh
t (in
grams
)
1-
30/1
2
25
almuglad
iv
iii
8/4
15/1
13/1
3/1
38
38+4
3166
3050
3300
2-
30/1
2
22
almuglad
ii
i
??
??
23/1
6/1
36+4
37+4
2942
2901
3100
3-
30/1
2
25
eldibab
iv
iii
11/
4
18/1
20/1
6/1
37
38
3157
3345
3000
4-
30/1
2
34
almuglad
v
iii
??
??
2/1
1/1
40+2
40+4
4117
3982
4200
5-
31/1
2
23
almuglad
iii
ii
8/4
15/1
23/1
6/1
36 +5
37+5
3034
3206
3100
6-
31/1
2
18
almuglad
ii
i
??
??
15/1
1/1
37+6
38
3116
3099
3200
7-
31/1
2
24
almairam
iv
iii
31/
3
6/1
7/1
4/1
39
39+4
3947
3867
4000
8-
1/1
30
almuglad
iv
iii
??
??
7/1
1/1
39+1
39+1
3700
3634
3800
9-
1/1
33
almuglad
iii
ii
20/
4
27/1
26/1
5/1
36+3
37
2760
2706
2900
10-
1/1
27
almuglad
v
iv
??
??
10/1
2/1
38+5
38+6
3371
3290
3400
11-
3/1
22
almuglad
iii
i
??
??
23/1
10/1
37+1
38+1
3112
3008
3000
12-
3/1
30
almairam
vii
v
??
??
24/1
9/1
37
37+6
3175
3450
3300
13-
3/1
18
adila
ii
0
??
??
23/1
10/1
37+1
38+1
3096
3357
3200
14-
4/1
33
altoboon
viii
vi
12/
4
19/1
21/1
11/1
37+4
38+4
3368
3500
3400
65
15-
4/1
20
almuglad
iii
ii
??
??
20/1
7/1
37+5
38+1
3247
3345
3100
16-
5/1
37
aldibab
x
ix
??
??
23/1
12/1
37+3
38+3
3257
3421
3300
17-
5/1
20
almuglad
iii
ii
??
??
25/1
11/1
37+1
38
3190
3456
3300
18-
6/1
31
kigeera
iii
ii
??
??
2/1
6/1
40+4
40+4
4223
4143
4400
19-
6/1
28
abulikri
vi
iv
??
??
19/1
10/1
38+1
38+5
3361
3098
3300
20-
7/1
24
almuglad
iv
iii
19/
4
26/1
28/1
14/1
37
38
3125
3234
3000
21-
7/1
22
almuglad
iii
ii
??
??
31/1
14/1
36+4
37+4
2790
2892
2600
22-
10/1
41
almgdma
viii
vii
??
??
19/1
10/1
38+5
38+5
3178
3223
3300
23-
10/1
25
almuglad
iii
i
9/4
16/1
18/1
14/1
38+6
39+3
3577
3643
3500
24-
10/1
30
eldibab
vi
iv
??
??
26/1
12/1
37+5
38
3390
3439
3200
25-
11/1
20
almairam
ii
i
10/
4
17/1
27/1
17/1
37+5
38+5
3373
3248
3500
26-
11/1
25
almuglad
iv
iii
18/
4
25/1
30/1
16/1
37+2
38
3110
3249
3000
27-
11/1
17
altoboon
i
0
11/
4
18/1
18/1
11/1
39
39
3501
3687
3500
28-
12/1
33
almuglad
vii
iv
??
??
26/1
12/1
38
38
3588
3602
3400
29-
12/1
26
almuglad
iv
iii
12/
4
19/1
2/2
19/1
37
38
3137
3089
3300
30-
12/1
30
altoboon
v
iv
??
??
12/1
17/1
40
40+5
4117
4247
4000
31-
12/1
15
almuglad
i
0
??
??
16/1
16/1
39+3
40
3664
4051
3800
32-
13/1
31
almuglad
vii
v
??
??
29/1
20/1
37+5
38+5
3067
3209
3000
33-
13/1
25
almagada
iv
ii
23/
4
30/1
9/2
20/1
36+1
37+1
2761
2702
2900
34-
14/1
38
eldibab
viii
v
??
??
22/1
16/1
38+6
39+1
3378
3428
3100
35-
15/1
30
eldibab
vi
v
20/
4
27/1
28/1
18/1
38+1
38+4
3496
3399
3500
66
36-
15/1
17
altoboon
ii
0
28/
4
5/2
6/2
21/1
36+6
37+5
3199
3007
3300
37-
17/1
18
almuglad
i
0
22/
4
31/1
1/2
18/1
37+6
38
3266
3490
3400
38-
20/1
20
almuglad
iii
ii
20/
4
27/1
31/1
20/1
38+3
38+3
3546
3671
3450
39-
20/1
30
almuglad
vi
iii
??
??
8/2
22/1
37+2
37+4
3081
3487
3240
40-
22/1
31
almairam
ix
viii
??
??
4/2
22/1
38+1
38+1
3343
3513
3300
41-
22/1
23
almuglad
iv
iii
31/
4
6/2
6/2
25/1
37+6
38+2
3285
3185
3400
42-
24/1
40
altoboon
viii
vii
??
??
11/2
30/1
37+3
38+2
3224
3295
3100
43-
24/1
20
almuglad
iv
iii
7/5
14/2
15/2
31/1
36+6
37+6
2937
2849
3250
44-
25/1
25
almagada
iii
ii
??
??
4/2
4/2
38+4
38+4
3676
3612
3800
45-
27/1
30
aldibab
vi
iv
??
??
11/2
30/1
37+6
38+2
3452
3398
3500
46-
2/2
24
almuglad
iv
ii
??
??
18/2
5/2
37+5
38+1
3315
3279
3200
47-
3/2
35
almuglad
vi
v
15/
5
22/2
24/2
10/2
37
38
3060
3261
3000
48-
3/2
30
almuglad
i
0
6/5
13/2
12/2
4/2
38+5
38+6
3537
3484
3600
49-
3/2
17
almairam
ii
i
??
??
10/2
3/2
39
39
3617
3603
3500
50-
7/2
35
almuglad
vii
vi
5/5
12/2
13/2
7/2
39+1
39+1
3698
3581
3700
51-
8/2
26
almgdma
iv
0
10/
5
17/2
20/2
8/2
38+2
38+2
3549
3479
3600
52-
12/2
20
almuglad
iii
ii
??
??
6/3
17/2
36+6
37+6
3008
3269
3100
53-
12/2
24
almuglad
iv
iii
??
??
5/3
19/3
37
38
3005
3168
2900
54-
14/2
30
altoboon
v
0
30/
5
5/3
8/3
21/2
36+6
37+6
2968
3247
3100
55-
16/2
25
almuglad
iii
ii
27/
5
3/3
2/3
18/2
38
38+2
3317
3289
3500
56-
16/2
35
almairam
v
iv
??
??
8/3
22/2
37+1
38
3023
2989
3200
67
57-
21/2
20
almuglad
ii
i
??
??
16/3
28/2
36+5
37+5
2970
3056
3200
58-
21/2
25
aldibab
iv
ii
??
??
19/3
28/2
36+2
37+2
2776
2698
3000
59-
22/2
30
almuglad
v
iv
??
??
12/3
27/2
37+3
38+1
3235
3189
3300
60-
23/2
19
almuglad
ii
i
27/
5
3/3
9/3
27/2
38
38+4
3359
3303
3500
61-
23/2
38
sharif
viii
vi
??
??
14/3
28/2
37+2
38
3253
3137
3300
62-
23/2
24
almairam
iv
ii
??
??
14/3
2/3
37+2
38+2
3097
2899
3200
63-
23/2
30
almgdam
a
v
iv
5/6
12/3
13/3
1/3
37+3
38+3
3207
3176
3100
64-
24/2
18
almuglad
ii
i
??
??
18/3
26/2
36+6
37+1
3086
3000
3300
65-
24/2
32
eldibab
vi
v
6/6
13/3
17/3
3/3
37
38
3003
3157
3000
66-
24/2
25
altboon
iv
iii
19/
5
26/2
28/2
24/2
39+3
39+3
3504
3494
3700
67-
25/2
22
almuglad
iii
0
??
??
22/3
4/3
36+3
37+3
2890
2816
3100
68-
26/2
16
alsitaib
i
0
??
??
16/3
4/3
37+3
38+3
3230
3341
3000
69-
28/2
34
almairam
viii
vi
??
??
20/3
6/3
37+1
38+1
3032
2994
3200
70-
28/2
20
kigera
ii
i
7/6
14/3
15/3
1/3
37+6
38
3343
3692
3500
71-
2/3
27
almuglad
iv
iii
1/6
8/3
12/3
2/3
38+4
38+4
3513
3661
3400
72-
2/3
31
altoboon
iv
iii
7/6
13/3
22/3
8/3
37+1
38
3029
2983
3200
73-
3/3
30
almuglad
vi
iv
??
??
27/3
10/3
36+4
37+4
3030
3007
3300
74-
3/3
20
aldibab
ii
i
??
??
31/3
8/3
36
36+5
2691
2567
2900
68
Figure 1 :Image of AC at 38 wks +3 days
Figure 2: Image of FL measurement
Figure 3: Image of BPD measurement
69
Figure 4: Image of FL at 40 wks +2 days
Figure 5: Image of BPD &HC AT 38wks+2 days
Figure 6: AC at 39 wks
70
Figure 7 : Image of BPD at 38 wks +1 day
Figure8 : AC at 38+6 days
Figure 9: FL at 37wks+ days
71
Figure 10: BPD at 37 wks +1 day
Figure 11: AC at 36wks +4 days
Figure 12: FL at 36wks +2 days
72
Figure 13: BPD at 37 wks +1 day
Figure 14: AC at 37wks +3 days
Figure 15: FL at 37wks +4 days
73
Figure 16: AC at 36wks+ 0 days
Figure 17: BPD at 37 wks + 6 days
Figure 18: FL at 37wks +1 day
74
Figure 19: AC at 37wks + 1 day
Figure 20: HC at 37wks+ 1 day
Figure 21: FL at 37 wks + 4 days
75
Figure 22: HC at 37 wks +3 days
Figure 23: FL at 37 wks + 1 day
Figure 24: FL at 37 wks + 4 days
76
Figure 25: HC at 37 wks + 3 days
Figure 26: FL at 37wks +3 days
Figure 27: BPD& HC at 37wks +4 days
77
Figure 28: AC at 37 wks+ 6 days
Figure 29: HC& BPD at 38wks
Figure 30: FL at 37wks +6days
78