RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, BANGALORE, KARNATAKA

PROFORMA FOR REGISTRATION OF SUBJECT FOR DISSERTATION

TOPIC

“ESTIMATION OF FOETAL WEIGHT USING SYMPHYSIOFUNDAL HEIGHT,ULTRASOUND AND ITS CORRELATION WITH ACTUAL BIRTH WEIGHT”

Dr. NIHARIKA M

POSTGRADUATE

DEPARTMENT OF OBSTETRICS & GYNAECOLOGY

K.V.G. MEDICAL COLLEGE & HOSPITAL

SULLIA. (D.K)-574327.

KARNATAKA.

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, BANGALORE

KARNATAKA

ANNEXURE – II

PROFORMA FOR REGISTRATION OF SUBJECT FOR DISSERTATION

1 / NAME OF THE CANDIDATE AND ADDRESS / Dr.M.NIHARIKA
DEPARTMENT OF OBSTETRICS AND GYNECOLOGY,
KVG MEDCIAL COLLEGE AND HOSPITAL,
SULLIA,D.K.
2 / NAME OF INSTITUTION / KVG MEDICAL COLLEGE AND HOSPITAL
KURUNJIBAGH,
SULLIA,D.K-574327
3 / COURSE OF STUDY AND SUBJECT / M.S.OBSTETRICS&GYNECOLOGY
4 / DATE OF ADMISSION TO COURSE / 28/05/2012
5 / TITLE OF TOPIC / “ESTIMATION OF FETAL WEIGHT USING SYMPHYSIOFUNDAL HEIGHT,ULTRASOUND & ITS CORRELATION WITH ACTUAL BIRTH WEIGHT”
6 / BRIEF RESUME OF THE INTENDED WORK
6.1 Need For Study:
Estimation of foetal weight at term is an important indicator of pregnancy outcome. Accurate estimation of weight is one of the most important factors in successful planning and management of labour and delivery1,2 and it is still a topic of great interest in obstetrics because abnormal labour and neonatal complications may be associated with higher or lower birth weights3,4 .
Evaluation of cephalopelvic disproportion before induction of labour,detection of intrauterine growth restriction and prevention of prematurity can be done by estimation of foetal weight before delivery5.
Estimating foetal weight antenatally is crucial as planning of preventive measures can be done when the obstetrician predicts an unwanted situation such as respiratory distress syndrome (RDS) or hypoglycemia in a low birth weight (LBW) neonate. Obstetricians can reduce the risk of mortality and morbidity of the mothers and neonates by referring them to a tertiary level2.
The two main methods for predicting birth weight in current obstetrics are:
(a) Clinical techniques based on abdominal palpation of fetal parts and calculations based on fundal height and
(b) Sonographic measures of skeletal foetal parts .
During the last decade, estimated foetal weight has been incorporated into the standard routine antepartum evaluation of high risk pregnancies,for instance management of diabetic pregnancy, delivery of a big baby, low-birth weight babies,vaginal birth after caesarean section and intrapartum management of foetuses presenting by breech will be greatly influenced by foetal weight6.
In situations where ultrasound facilitates are not available which is the most common problem in rural places in developing countries like India we require a easy, quick clinical method for estimation of foetal weight in utero which will be of benefit to the birth attenders and paramedical staff working in rural areas as still in many places home deliveries are being conducted. This will be useful for referring them to higher centers for better management7.
Foetal weight estimation is most important in decision making and has prognostic value in the obstetrics especially in LBW babies, preterm, LGA babies. Methods used for foetal weight estimation are:
1.  Johnson’s formula (weight in grams) 8,9,10
Estimated weight(gms)=155(Symphysiofundal height-X)
X=12 ,if the vertex is at or above the of Ischial spines
X=11 ,if the vertex is below the level of ischial spines
2. Ultra sound method:
Hadlock’s formula 11:
Log10EFW=1.3596-0.00386(AC X FL)+ 0.0064(HC)+
0.00061(BPD X AC)+0.0425(AC)+0.174(FL)
The accuracy of weight prediction formula improves as the number of foetal
parameters increase up to four.
Knowledge of expected birth weight is important to the clinician as it is an important variable affecting perinatal mortality.
Abdominal circumference (AC) is the most accurate diagnostic measurement to predict SGA11.
Serial measurement of AC or EFW is superior for prediction of IUGR.
Maternal & Foetal risks associated with delivery of an excessively large foetus are :
·  Prolonged labour
·  Increased operative delivery
·  Increased morbidity and mortality in mother and foetus
·  Post partum hemorrhage
·  Shoulder dystocia with brachial plexus injury
·  Clavicle fracture
·  Ultrasound is helpful in predicting not only estimated foetal weight but also other parameters important in mode of delivery:
Foetal anomalies and abnormalities
Placental location
Amniotic fluid
Presenting part
Biophysical profile
Under the following conditions there is difficulty in estimating foetal weight clinically:
Obesity12
Polyhydramnios
Oligohydramnios
Uterine anomalies
Abnormal presentation
Abnormal Placental location
6.2 Review of literature:
A prospective study was conducted at Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria, between 3 January and 31May 2004, to compare the accuracy of clinical and ultrasonographic estimation of foetal weight at term. They found that clinical estimation of birth weight is as accurate as routine ultrasonographic estimation, except in low birth weight babies. Therefore when clinical method suggests weight less than 2,500 g, subsequent ultrasound estimation is recommended to yield better prediction and to further evaluate foetal well-being1.
A randomized clinical trial was conducted in term parturients to compare clinical versus sonographic estimation of birth weight. This study concluded that among term parturients clinical estimates had significantly higher accuracy than once derived foetal weight sonograhically13.
A prospective study was done to assess the association between fundal height measurement for foetal weight estimation and actual birth weight by Fatemeh Ghaemmaghami MD, , Ashraf Jamal MD, Mohammad-Reza Soleimani MD, Hooman Mohammadian, MD and found that for actual birth weights in the normal range, our results showed that the normal range of fundal height was 27 to 35 centimeters. For a fundal height measurement outside of this range, an abnormal and a high-risk delivery should be expected2.
A prospective study was conducted to compare the accuracy of clinical and sonographic estimation of foetal weight in pregnant women and found that intrapartum clinical estimation of foetal weight was accurate as sonographic estimation and clinical estimation is good enough for screening of the low-birth weight because of its high sensitivity and negative predictive value3.
A prospective study was conducted of the accuracy of foetal weight estimation
comparing clinical and ultrasound estimation with actual birth weight in 200 Iranian pregnant women. Study indicates that the mean clinical estimate of foetal weight is equal to ultrasound for the estimation of foetal weight in our population. This has important implications for developing countries where there is a lack of technologically advanced ultrasound machines capable of performing sophisticated functions like foetal weight estimation14.
A retrospective study was conducted to assess the accuracy of symphysis pubis fundal height measurement and ultrasound derived estimation of foetal weight for identifying small for weight gestational age and low for weight gestational age fetuses.they found that although ultrasound has a slightly increased sensitivity, neither clinical examination using fundal height measurement nor 3rd trimester ultrasound examinations are effective at detecting small for gestational age or large for gestational age fetuses15.
In 1954 Johnson and Joschach studied 200 cases for estimating foetal weight using symphysiofundal height and abdominal girth8,9.
The advent of USG gave a breakthrough in estimating foetal weight as it was noninvasive, non hazardous and reliable. Foetal biometry gradually developed and several parameters were used. The most important sonological foetal parameters which withstood the test of time are
abdominal circumference
biparietal diameter
femoral length
head circumference
Greatest accuracy is achieved by the combination of these parameters up to 4.In macrosomic foetuses the weight is underestimated. For low birth weight fetuses Shepard formulae is more accurate11.
For very low birth weight foetus Hadlock’s equation showed more accurate estimation16. Hadlock’s formula was originally designed for American population but also suitable for Southasian population 17.
6.3 Objective of the study:
1.To assess the foetal weight in term pregnancies by
Johnsons formula, Hadlocks formula using ultrasound
2.To correlate actual foetal weight with the foetal weight obtained by these two methods.
7 / MATERIALS AND METHODS:
7.1 Source of data:
Singleton pregnancies of 37 weeks and above fulfilling the inclusion and exclusion criteria.
7.2 Method of collection of data
Study place:
KVG MEDICAL COLLEGE AND HOSPITAL,
KURUNJIBAGH,
SULLIA,D.K
Study period:
FROM 1st DECEMBER 2012 to 30thNOVEMBER 2013
Sample size:100
Sample design: Randomized sampling
Procedure:
A total no of 100 patients are included in the study.
Patients are counseled and explained that the obstetric scan is routine and is noninvasive and safe procedure. The relevant parameters are recorded as per the proforma which includes:
The identification data
Demographic characteristics
General physical examination and obstetric examination.
All pregnant women admitted to the labour ward at term more than or equal to 37 weeks with a singleton pregnancy preferably cephalic presentation and intact membranes are eligible. Spontaneous labour as well as those admitted for elective induction or caesarean section are included.
Patient is then asked to empty her bladder and the resident will measure the symphysiofundal height and abdominal girth in between contractions using a flexible, non-elastic standard sewing tape. Patient is lying flat on her back with her legs extended.
Fundal height was measured from the midpoint of the upper border of pubic symphysis to the highest point of the uterine fundus.
A pelvic examination is then performed to evaluate cervical dilatation, degree of descent of foetal head, its station and presence of intact membranes.
The foetus will be considered to be at minus station when the lowermost portion of foetal head is above the ischial spines, at zero station when the head is at the level of ischial spines and at plus station when the head is below the ischial spines.
Then ultrasound is done to estimate foetal weight using hadlock’s formula which uses BPD.AC and FL.Also amniotic fluid and placental evaluation is done using Mindray Digital Ultrasonic Diagnostic Imaging System.Model-DP-6600.Real time ultrasound scan is used to calculate EFW by Hadlock’s method. Equipment is grey scale real time ultrasound scanner with 3.5MHz transducer.
Biparietal diameter was measured with electronic calipers on the frozen image from outer edge of the proximal skull to the inner edge of the distal skull table.
Head circumference was measured using ellipse method by tracing head circumference along the outer table at the same level.
Abdominal circumference was measured at the level of umbilical vein as it enters the liver. Femur length measured from greater trochanter to external condyle excluding femoral head. Birth weight was recorded immediately after delivery.
Inclusion criteria:
All singleton pregnancies between 37-42 weeks.
Age 18 & above
Cephalic presentations
Booked case
Intact membranes
Patient with dating scan or with reliable date.
Exclusion criteria:
Multiple gestation
Preterm
Foetal anomalies
Polyhydramnios
Maternal diabetes mellitus
Fibroid uterus
Oligohydramnios
Follow up: No
Follow up period: Nil
7.3 Does the study require any investigations or interventions to be conducted on patients or other humans or animals? Yes.
INVESTIGATIONS:
Along with all the routine obstetric investigations ultrasound at 18-20 wks and ultrasound within 24hrs of delivery.
INTERVENTIONS: Nil.
7.4 Has ethical clearance been obtained from your institution in case of 7.3?
Yes. Copy enclosed