Comparative Study of Methods of Fetal Weight Estimation

Comparative probe of Methods of Fetal tip EstimationINTRODUCTIONKnowledge of fetal load in utero is important for the obstetricalian to steady down whether or not to deliver the fetus and also to decide the mode of delivery. Both pocket-size-toned stock weighting and excessive fetal weight at delivery are associated with increased hazard of newborn baby complications during labor and the puerperium. versatile clinical expressione like Johnsons dominion and Dawns formula have come into work for fetal weight estimation. An otherwise(a) formula is the product of symphysiofundal bill with abdominal muscle girth in centimeters which gives a fairly good estimate of fetal weight.METHODSIt is a prospective empiric study of 200 women at stipulation pregnancy at a hospital.Patients within 15 long time from their judge Date of Delivery were included in the study. The formulas utilize in this study areJOHNSONS edictSYMPHYSIOFUNDAL HEIGHT X ABDOMINAL GIRTH (AG X SFH)DAWNS FO RMULAHADLOCKS FORMULA USING ULTRASOUND.RESUTLSThere have been differing results about accuracy of various systems of estimating fetal weight. This study showed that AG X SFH was the best indicator among on the whole other methods assessed followed by Hadlocks formula by ultrasonographic method. culminationFundal height assessment is an inexpensive method for screening for fetal crop limit. SFH cadence continues to be used in many a(prenominal) countries on large scale because of its low cost, ease of use, and need for little formulation as the setup for ultrasonographic evaluation is not readily available in rural setups.KEYWORDS Fetal Weight, At Term Pregnancy, Symphysiofundal Height, Ultrasonography, Newborn ComplicationsINTRODUCTIONKnowledge of fetal weight in utero is important for the obstetrician to decide whether or not to deliver the fetus and also to decide the mode of delivery. Both low birth weight and excessive fetal weight at delivery are associated with an incr eased risk of newborn complications during labor and the puerperium. The perinatal complications associated with low birth weight are attributable to preterm delivery, intrauterine growth restriction (IUGR), or both(prenominal). For excessively large fetuses, the potential complications associated with delivery include shoulder dystocia, brachial plexus injuries, sense slight injuries, and intrapartum asphyxia. The maternal risks associated with the delivery of an excessively large fetus include birth canal and pelvic write up injuries and postpartum hemorrhage. The occurrence of cephalopelvic disproportion is more prevalent with increasing fetal size and contributes to both an increased tempo of operative vaginal delivery and cesarean delivery for macrosomic fetuses compared with fetuses of normal weight. Estimation of fetal weight beingness done clinically has received much criticism for less accuracy due to observer variation.Various clinical formulae like Johnsons formula a nd Dawns formula have come into usage for fetal weight estimation. Another formula is the product of symphysiofundal height with abdominal girth in centimeters which gives a fairly good estimate of fetal weight.AIMS AND OBJECTIVESThe aim of this study was to assess the fetal weight in term pregnancies by various methods- abdominal girth (cms) X symphysiofundal height (cms) AG X SFH, Johnsons formula, Dawns formula and Hadlocks formula using ultrasound, and to compare the methods afterwards knowing the literal weight of the baby after birth.MATERIALS AND METHODSIt is a prospective observational study of 200 women at term pregnancy at Dhiraj General Hospital, Vadodara from 1st June 2010 to 31st May 2011. Patients within 15 days from their Expected Date of Delivery were included in the study.Cases of MULTIPLE PREGNANCIES, OLIGO/POLYHYDRAMNIOS, MALPRESENTATIONS AND FIBROID OR ADNEXAL MASSES were excludedTHE METHODSJOHNSONS FORMULASYMPHYSIOFUNDAL HEIGHT X ABDOMINAL GIRTH.DAWNS FORMULAH ADLOCKS FORMULA USING ULTRASOUND.JOHNSONS FORMULAWEIGHT IN GRAMS = (SYMPHYSIOFUNDAL HEIGHT x) X 155.Here symphysiofundal height is taken after correcting the dextrorotation, from the amphetamine border of symphysis to the height of the fundus.station of the head was notedx = 12 when head was at or above the level of the ischial spinesx = 11 when head was below the level of ischial spines.AG X SFHWeight in grams = abdominal girth (AG) x symphysiofundal height (SFH) (AG X SFH)Abdominal girth was measured at the level of umbilicus and symphysiofundal height as described earlier.DAWNS FORMULAWEIGHT IN GRAMS =Longitudinal diameter of the uterus x (transverse diameter of the uterus)2 x 1.442HADLOCKS FORMULA by and by head circumference, abdominal circumference and femur length were measured in centimeters, the sonography machine mensurable the fetal weight.Fetal weight estimated by the above four methods was compared with the actual weight of the baby after birth. A comparative analysis of the four methods was done.OBSERVATION AND RESULTSTABLE I WEIGHT WISE statistical distributionTABLE II AVERAGE ERROR IN CALCULATION OF foetal WEIGHT IN mingled GROUPSAverage error in all fetal weight groups except in 3500 gms was least with AG X SFH closely followed by Hadlocks ultrasound method.Average error in 3500 gms group was least with Johnsons formula.TABLE III NUMBER OF CASES UNDERESTIMATED AND OVERESTIMATED IN VARIOUS FORMULASNumber of over and under-estimations in all fetal weight groups was calculated.AG X SFH and Dawns formula had a tendency to underestimate. The other 2 methods overestimated.In 3500 gms group, all methods underestimated.TABLE IV MAXIMUM ERROR IN ALL FETAL WEIGHT GROUPSMost marked with Dawns and least with AG X SFH.By both these methods maximum error was in the 3001- 3500 gms group.By Johnsons formula, maximum error was in the TABLE V PERCENTAGE ERROR IN VARIOUS METHODSPercentage error was calculated usingx/y x 100x= error in gramsy= birth weigh t in gramsAs seen in the table, 85.5% cases came within 15% of actual birth weight by both Hadlocks and AG X SFH methods.As compared to only 50% and 63.5% by Dawns and Johnsons formula, respectively.TABLE VI STANDARD DEVIATION OF PREDICTION ERRORThe standard deviation of prediction error was least with Hadlocks formula, closely followed by AG X SFH.It is much higher with Dawns and Johnsons formulae.The sport amongst the four methods was statistically different. p measure out DISCUSSIONBirth weight is a rudimentary variable affecting fetal and neonatal morbidity, particu- larly in preterm and small-for-dates babies. In addition, it is of value in the management of rear of tube presentations, diabetes mellitus, trial of labour, macrosomic fetuses and multiple births.Clinicians estimates of birth weight in term pregnancy were as accurate as routine ultrasound estimation in the week before delivery. Furthermore, parous womens estimates of birth weight were more accurate than either clinical or ultrasound estimation.There have been differing results about the accuracy of the various methods of estimating fetal weight.This study showed that AG X SFH was the best indicator among all of the other methods assessed followed by Hadlocks formula by ultrasonographic method.Other studies have reported limited accuracy of ultrasound EFW at term, particularly in macrosomic fetuses but over all accuracy of this formula is same for all infants. outfit with information about the fetal weight the obstetrician managing labour is able to pursue sound obstetric management, reducing perinatal morbidity and mortality.Symphysiofundal height is one of the important clinical parameters taken for fetal weight estimation by AG X SFH, Johnsons formula, Dawns formula.According to my study, Hadlocks ultrasonographic method was the close to accurate for estimating fetal weight.Of the three clinical methods, AG X SFH has better predictable results than the other 2 methods.AG X SFH, a clin ical formula can be of great value in a developing country like ours where ultrasound is not available at many health care delivery centres.It is easy and simple, can be used even by midwives. With less errors AG X SFH is easier to apply by paramedical workers for the evaluation of fetal weight even in the rural setup as like our area of this study. By this study the results are suggesting that Hadlocks formula has least standard deviation but it requires ultrasonographic evaluation. So after it, AG X SFH is the second most formula for estimation of featl weight which is clinically applicable and most tested method in the absence of sonologic setup.CONCLUSIONFundal height assessment is an inexpensive method for screening for fetal growth restriction.1 Clinicians are colored in their fundal height measurements by knowledge of gestational age and use of a marked measuring rod tape. This tendency increases with higher patient BMI and with less provider experience.2 While we have ye t to establish reliable tests to predict which pregnancies are at risk of developing IUGR, surveillance of fetal growth in the three trimester of pregnancy continues to be the mainstay for the assessment of fetal well-being. Such surveillance is done by unceasing fundal height assessment, ultrasound biometry or a combination of both methods.3 Relative growth of the SF height seems to be independent of fetal sex, maternal obesity and parity.4 There is disagreement in SFH measurement between observers regarding the ability to separate small fundal heights from those that are not small (Bailey 1989). This becomes an issue especially in a clinical setting where the pregnant woman sees more than one clinician during the course of her pregnancy. Despite this, SFH measurement continues to be used in many countries on a large scale simply because of its low cost, ease of use, and need for very little training.5 Ultrasound evaluation of fetal growth, behavior, and measurement of impedance to crosscurrent flow in fetal arterial and venous vessels form the cornerstone of evaluation of fetal ascertain and decision making.6REFERENCES1).Morse K, Williams A, Gardosi J (December 2009). Fetal growth screening by fundal height measurment.2).Jelks A, Cifuentes R, Ross MG (October 2007) Clinician bias in fundal height measurement.3).Gardosi Francis 1999, Morse et al 2009. Standardised protocol for measurment of symphysio fundal height4).Bergman E, Axelsson O, Kieler H, Sonesson C, Petzold M. Relative growth for estimation of intrauterine growth retardation. . Submitted. 2010.5).Robert Peter J, Ho J, Valliapan J, Sivasangari S. Symphysial fundal measurement (SFH) in pregnancy for detecting abnormal fetal growth (Protocol). The Cochrane Library. 2009(Issue 4).6).Resnik R. Intrauterine growth restriction. Obstet Gynecol. 2002 March.