Ultrasonographic Estimation Of Fetal Weight Research Articles

Correlation Between Ultrasonographically Estimated Fetal Weight and Actual Birth Weight in Females Presenting in a Tertiary Care Hospital

Objective: To determine the correlation between ultrasono-graphically estimated fetal weight and actual birth weight in females presenting in a tertiary care hospital.
 Study Design: Comparative cross-sectional study.
 Place and Duration of Study: Department of Radiology Peripheral Nervous System, PNS Shifa Hospital Karachi Pakistan, from Sep 2018 to Jan 2019.
 Methodology: Fifty pregnant females were enrolled after meeting the inclusion criteria. A consultant radiologist calculated fetal weight by measuring biparietal diameter (BPD), head circumference (HC), femur length (FL) and abdominal circumference (AC) with the help of an ultrasound (USG) machine having a Hadlock 3 weight estimation algorithm. A paediatrician noted actual birth weight with a weighing scale after delivery.
 Results: The mean fetal weight on ultrasound was 2.52±0.34kg. The mean actual birth weight of the babies was 2.66±0.42 kg. A strong positive correlation (r=0.575, p<0.05) was found between ultrasonographic fetal weight estimation and actual birth weight.
 Conclusion: Ultrasonography is an accurate, safe, cost-effective and easy available imaging modality for fetal weight estimation.

Trial of labor after cesarean delivery for estimated large for gestational age fetuses: A retrospective cohort study

ObjectiveAlthough ultrasonographic estimation of fetal weight ≥90th percentile is not associated with a greater risk for uterine rupture, trial of labor after cesarean delivery (TOLAC) is considered relatively contraindicated for macrosomic fetuses. Hence, when an estimated fetal weight of 4000 g is detected, TOLAC is usually avoided.Our aim was to evaluate the obstetrical outcome and safety of TOLAC in women with estimated large for gestational age fetuses (eLGA) (≥90th percentile). Study DesignOur retrospective cohort study encompassed all pregnant women with an estimated fetal weight ≥90th percentile for gestational age, admitted to a single tertiary care center between January 2012-July 2017 for TOLAC. Results1949 women met the inclusion criteria; 78 (4%) eLGA and 1871 (96%) controls. Fifty-five (70.5%) women in the study group had experienced a successful vaginal delivery compared to 1506 (80.5%) of the controls (p = 0.03). The rate of obstetrical complications, including scar dehiscence, uterine rupture, a 3rd/4th degree perineal tear or shoulder dystocia were comparable. The rate of post-partum hemorrhage (PPH) increased in the study group compared to the controls (7.7 % vs.1.7%; p = 0.001). ConclusionTOLAC for eLGA fetuses can be considered safe, however, lower successful rates of vaginal births after a cesarean delivery and an increased PPH rate, may be expected.

Vacuum-Assisted Delivery Complication Rates Based on Ultrasound-Estimated Fetal Weight.

This retrospective cohort study investigated the association between ultrasonographic estimated fetal weight (EFW) and adverse maternal and neonatal outcomes after vacuum-assisted delivery (VAD). It included women with singleton pregnancies at 34–41 weeks gestation, who underwent ultrasonographic pre-labor EFW and VAD in an academic institution, over 6 years. Adverse neonatal and maternal outcomes included shoulder dystocia, clavicular fracture, or third- and fourth-degree perineal tears. A receiver–operator characteristic curve was used to identify the optimal weight cut-off value to predict adverse outcomes. Fetuses above and below this point were compared. Multivariate analysis was used to control for factors that could lead to adverse outcomes. Eight-hundred and fifty women met the inclusion criteria and had sonographic EFW within two-weeks before delivery. Receiver–operator characteristic curve analysis found that ultrasonographic EFW 3666 g is the optimal threshold for adverse outcomes. Based on these results, outcomes were compared using EFW 3700 g. The average EFW in the ≥3700 g group (n = 220, 25.9%) was 3898 ± 154 g (average birthweight 3710 ± 324 g). In the group <3700 g (n = 630, 74.1%), average EFW was 3064 ± 411 g (birthweight 3120 ± 464 g). Shoulder dystocia and clavicular fractures were more frequent in the higher EFW group (6.4% and 2.3% vs. 1.6% and 0.5%, respectively; p < 0.05). Women in the ≥3700 g group experienced more third- and fourth-degree perineal tears (3.2% vs. 1%, p = 0.02). Multivariate logistic regression analysis found maternal age, diabetes and sonographic EFW ≥ 3700 g as independent risk-factors for adverse outcomes. Sonographic EFW ≥ 3700 g is an independent risk-factor for adverse outcomes in VAD. This should be considered when choosing the optimal mode of delivery.

Factors Affecting Ultrasonographic Fetal Weight Estimation Accuracy in Low Birth Weight Newborns

Objective: To investigate the accuracy of fetal weight estimation made by the last prenatal ultrasound measurement in low birth weight newborns (&lt;2500 g). Study Design: A total of 1082 women were evaluated in this retrospective cohort study. Demographic and clinical information of the mother and newborn and obstetric ultrasonography measurements and findings performed in the last week before birth were recorded. Accuracy of fetal weight estimation and parameters affecting it was investigated. Results: Accurate estimation rates were lower in the term compared to the preterm delivery group; and in the SGA group compared to the AGA group (respectively, p=0.016, p=0.032). Accurate estimation rates (p=0.182) were comparable between the 500-1500 g and 1501-2500 g subgroups. The multiple linear regression analysis showed that gestational age at birth, birth weight, examination during labor, and duration between examination to delivery were statistically significant for the accurate estimation(p=0.001) Conclusions: Accurate estimation rates were lower in the term compared to the preterm delivery group, and in the SGA group compared to the AGA group. The factors affecting accurate estimation were found to be gestational age at birth, birth weight, examination during labor, and duration between examination to delivery.Keywords: Accurate estimation rate, Duration between examination to delivery, Examination during

Determination of error level of ultrasonographic fetal weight estimation according to the seniority of residents in obstetrics and gynecology

Objectives: We consider the difference between estimated fetal weight and birth weight through the measurement according to the seniority of the residents in obstetrics and gynecology. In this study, we aimed to determine the fallibility of the residents according to their seniority years.Methods: This research was planned as a prospective and approved by the Ethics Committee Ultrasonographic measurements were performed with ultrasound device and the estimated fetal weight was calculated with Hadlock 4 (BPD, HC, AC, FL) formula. Measurements were performed by the residents in the first, second, third and fourth year of training and repeated by the same specialist for each patient. Only those who gave birth within 48 hours of the ultrasonographic measurements were included in the study.Results: A total of 392 pregnant women were included in the study. Ninety-eight pregnant women were examined by 1st year resident, 100 pregnant by 2nd year resident, 93 pregnant by 3rd year resident and 101 pregnant by 4th resident. Largest difference between the estimated fetal weight and birth weight was performed by the fourth year resident with 125.06 ± 247.40 grams.Conclusions: The estimated fetal weight by ultrasonography has an important place in obstetric practice and it may vary according to the years of seniority of the resident. For this reason, ultrasonography should be used effectively and accurately during the training of the residents in the centers of education in obstetrics and gynecology and it is essential that the residents learn the ultrasound examination properly and completely.

Comparison between clinical estimated fetal weights (CEFW) Versus Ultrasonographic estimated fetal weight (UEFW) for co-relation with actual birth weight (ABW) in 3rd Trimester of Pregnancy

Background: Accurate prenatal estimation of birth weight is useful in the management of labour and delivery. &#x0D; Objective: To determine the correlation between clinical estimated fetal weight with actual birth weight in 3rd trimester of pregnancy and to determine the correlation between Ultrasonographic fetal weight assessment with actual birth weight in 3rd trimester of pregnancy.&#x0D; Material &amp; Methods: This cross sectional study with non-probability purposive sampling technique was conducted in three tertiary care hospitals of Punjab, Department of Obstetrics &amp; Gynaecology, Allied Hospital, Faisalabad, Lady Aitcheson Hospital Lahore and Lady Willington Hospital Lahore. Informed consent was obtained from each female to use their data for research purpose. Demographic details were also noted. Then females undergo CEFW was done by using Johnson’s formula. Then ultrasonography was done on every female by experienced radiologists to get UEFW. FW measurement was done by using Shepard formula. Then females were followed-up till delivery of fetus. Actual birth weight (ABW) was noted on birth. Pearson correlation was used to measure the correlation coefficient for CEFW and UEFW with ABW. P-value≤0.05 was taken as significant.&#x0D; Results: In our study the mean age of the patients was 29.60±6.23 years and the mean gestational age of 33.30±2.31 weeks. The mean BMI value of the patients was 23.08±1.26 Kg/m2, the mean CEFW value 2219.60±556.41 grams while the mean UEFW value of the patients was 2227.77±521.94 grams and the mean value of ABW of the patients was 2284.00±515.29 grams. In our study the positive correlation was found between the CEFW, UEFW with ABW of the baby.&#x0D; Conclusion: Our study results concluded that both the clinical estimation ultrasonography estimation showed the feasible and reliable results. Both showed positive correlation with actual birth weight.

Correlation of Ultrasonographic Estimation of Fetal Weight with Actual Birth Weight as Seen in a Private Specialist Hospital in South East Nigeria

Background Ultrasound estimation of fetal weight at term provides vital information for the skilled birth attendants to make decisions on the possible best route of delivery of the fetus. This is more pertinent in a setting where women book late for antenatal care. Aim and Objectives The study evaluated the accuracy of estimation of fetal weight with ultrasound machine at term. Methods This was a cross sectional study conducted at a private specialist hospital in Nigeria. A coded questionnaire was used to retrieve relevant information which included the last menstrual period, gestational age, parity, and birth weight. Other information obtained includes Ultrasound-delivery interval, maternal weight, and route of delivery. The ultrasound was used to estimate the fetal weight. The actual birth weight was determined using a digital baby weighing scale. The data were inputted into Microsoft excel and analyzed using STATA version 14. Statistical significance was considered at p-values less than 0.05. Measures of accuracy evaluated in the statistical analysis included mean error, mean absolute error, mean percentage error, and mean absolute percentage error. Pearson correlation was done between the estimated ultrasound fetal weight and the actual birth weight. The proportion of estimates within ±10% of actual birth weight was also determined. ResultA total of 170 pregnant women participated in the study. The mean maternal age was 30.77 years ± 5.54. The mean birth weight was 3.47 kg ± 0.47, while the mean estimated ultrasound weight was 3.43 kg ± 0.8. There was positive correlation between the ultrasound estimated weight and the actual birth weight. The mean ultrasound scan to delivery interval was 0.8 days (with range of 0–2 days). The study recorded a mean error of estimation of 41.17 grams and mean absolute error of 258.22 grams. The mean percentage error was 0.65%, while the mean absolute error of estimation was 7.56%. About 72.54% of the estimated weights were within 10% of the actual birth weight. Conclusion The ultrasound estimated fetal weight correlated with the actual birth weight. Ultrasound estimation of fetal weight should be done when indicated to aid the clinician in making decisions concerning routes of delivery.

Could masking gestational age estimation during scanning improve detection of small-for-gestational-age fetuses? A controlled pre–post evaluation

Antenatal detection of small-for-gestational-age fetuses improves outcomes and reduces perinatal mortality rates. However, ultrasonographic estimation of fetal weight is subject to several potential sources of error. One potential source of error is subconscious operator bias towards "normal" measurement values for gestational age (observer-expectancy bias). We aimed to determine whether the sensitivity of small-for-gestational-age detection is improved by removing real-time display of estimated gestational age during measurement of the abdominal circumference in the third trimester. This retrospective evaluation (November 2014-May 2018 inclusive) included all singleton infants liveborn at ≥28 weeks gestation in a single United Kingdom obstetrics center. In the preintervention phase, real-time estimated gestational age was displayed to sonographers as they measured fetal abdominal circumference (the key determinant of estimated fetal weight with the use of the INTERGROWTH 21st fetal weight equation) in the third trimester. In the postintervention phase, real-time gestational age information was removed on selected ultrasound machines. Accuracy of birthweight percentile estimation was assessed before and after intervention, both in the full cohort comprising all eligible scans and in a subcohort that was scanned within 4 weeks of delivery. We assessed the accuracy of small-for-gestational-age detection using the sensitivity, positive likelihood ratio, and area under the receiver-operator curve. Of the 18,342 eligible pregnancies, 9342 (51%) had a third-trimester growth scan. The sensitivity of ultrasonographic estimation of fetal weight for antenatal detection of small-for-gestational-age babies did not change significantly between the before and after intervention phases (31.5% confidence interval, 27.1-36.2 vs 31.7% confidence interval, 20.2-45.0). Although the sensitivity for small-for-gestational-age detection was higher in the subcohort that was scanned within 4 weeks of delivery than in the full cohort (P<.001), there was no significant difference between the before and after intervention phases (58% confidence interval, 50-66 vs 65% confidence interval, 43-84). With the use of an estimation of the abdominal circumference percentile rather than estimated fetal weight percentile significantly decreased the sensitivity for small-for-gestational-age detection in all groups (P<.01), but there was no difference between the before and after intervention phases. Blinding operators to the estimated gestation of the fetus during abdominal circumference measurement does not significantly alter the antenatal detection rate of small-for-gestational-age babies. The observer-expectancy effect is therefore unlikely to be a significant contributor to the error that is associated with ultrasonographic estimation of fetal weight.

869: Can we improve ultrasonographic estimation of fetal weight by reducing operator bias?

To evaluate whether removing real-time display of an estimated gestational age (GA) during third trimester measurement of fetal abdominal circumference (AC) may improve (i) the accuracy of fetal weight estimation (EFW) or (ii) detection of small-for-gestational age (SGA) babies. A prospective interventional study over a 4-year period at a single tertiary UK obstetrics center. In the initial period (Oct 2014-Oct 2017) a standard scan protocol was operated, with real-time information regarding estimated GA displayed. In the intervention period (after Oct 2017) we altered presets on a number of ultrasound machines to withhold estimated GA information from the operator. Other machines were left unchanged as negative controls. The accuracy of EFW and detection rate of SGA (birth weight (BW) <10th centile) were compared before and after the intervention. 18342 deliveries were included, of which 9342 had third-trimester scans. 6432 scans were performed on intervention machines before the switch in scan protocol, and 1178 after. The average discrepancy between EFW centile and actual BW centile was unchanged by the intervention; 3.0 centiles (SD ±21.6) before compared to 2.7 centiles (SD ±20.9) afterwards. The sensitivity for antenatal detection of SGA remained unchanged at 31.5% (CI:27- 36%) before the intervention compared to 31.6% (CI:20-44%) afterwards, with a non-significant increase in the positive likelihood ratio from 18.2 (CI:14.4-23.1) to 19.4 (CI:10.9-35.5). The area under the ROC curve for the detection of SGA using EFW at 36 weeks improved from 0.91 to 0.94, but this difference was not statistically significant (p=0.25, Figure 1), nor was any improvement in detection of SGA using other measured parameters (Table1). Blinding operators to the estimated GA during scanning does not significantly improve concordance between EFW centile and actual BW centile, and does not significantly increase the antenatal detection rate of SGA babies.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Ultrasonographic estimation of fetal weight: development of new model and assessment of performance of previous models.

To develop a new formula for ultrasonographic estimation of fetal weight and evaluate the accuracy of this and all previous formulae in the prediction of birth weight. The study population consisted of 5163 singleton pregnancies with fetal biometry at 22-43 weeks' gestation and live birth of a phenotypically normal neonate within 2 days of the ultrasound examination. Multivariable fractional polynomial analysis was used to determine the combination of variables that provided the best-fitting models for estimated fetal weight (EFW). A systematic review was also carried out of articles reporting formulae for EFW and comparing EFW to actual birth weight. The accuracy of each model for EFW was assessed by comparing mean percentage error, absolute mean error (AE), proportion of pregnancies with AE ≤ 10% and Euclidean distance. The most accurate models, with the lowest Euclidean distance and highest proportion of AE ≤ 10%, were provided by the formulae incorporating ≥ 3 rather than < 3 biometrical measurements. The systematic review identified 45 studies describing a total of 70 models for EFW by various combinations of measurements of fetal head circumference (HC), biparietal diameter, femur length (FL) and abdominal circumference (AC). The most accurate model with the lowest Euclidean distance and highest proportion of AE ≤ 10% was provided by the formula of Hadlock et al., published in 1985, which incorporated measurements of HC, AC and FL; there was a highly significant linear association between EFW and birth weight (r= 0.959; P< 0.0001), and EFW was within 10% of birth weight in 80% of cases. The performance of the best model developed in this study, utilizing HC, AC and FL, was very similar to that of Hadlock et al. CONCLUSION: Despite many efforts to develop new models for EFW, the one reported in 1985 by Hadlock et al., from measurements of HC, AC and FL, provides the most accurate prediction of birth weight and can be used for assessment of all babies, including those suspected to be either small or large. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Comparison between Three Methods of Fetal Weight Estimation during the Active Stage of Labor Performed by Residents: A Prospective Cohort Study

Objective: To compare the accuracy of ultrasonographic, calculated, and clinical methods for the estimation of fetal weight (EFW) performed during active labor by residents. Methods: Parturients in active labor underwent prospectively EFW by 3 methods: ultrasonographic, clinical, and calculated (extrapolating EFW from a previous scan). Three different blinded residents evaluated each woman. Background variables were examined for their effect on the accuracy of each method. Comparison of the methods for the detection of macrosomia and small for gestational age (SGA) was also performed. Results: Among the 405 women recruited, the rates of accuracy of ultrasonographic, clinical, and calculated EFW (within ±10%) was 72.5, 74.3, and 71.1%, respectively. The correlation coefficient between the methods and actual birth weight (ABW) were 0.702-0.611 (using 7 Hadlock formulas), 0.649, and 0.622, respectively (all p < 0.001). By logistic regression, epidural analgesia was associated with higher and second stage of labor with lower accuracy of ultrasonographic EFW. For the detection of macrosomia, clinical (p < 0.001) and calculated EFWs (p = 0.035) were superior to ultrasonographic EFW. For the detection of SGA, ultrasonographic EFW was superior to calculated (p < 0.001) and clinical (p < 0.001) EFWs. Conclusion: All 3 methods performed by residents during labor correlated well with ABW. Clinical and calculated EFWs were superior for macrosomia detection, whereas ultrasonographic EFW was superior for SGA detection.

Effect of Parity, Maternal Body Mass Index, Maternal Weight Gain During Pregnancy, Stage of Labor, and Amniotic Fluid Volume on Ultrasonographic Estimation of Fetal Weight

Effect of Parity, Maternal Body Mass Index, Maternal Weight Gain During Pregnancy, Stage of Labor, and Amniotic Fluid Volume on Ultrasonographic Estimation of Fetal Weight

Comparison of ultrasonographic estimated fetal weight and actual birthweight performed by residents in training at the university hospital of the west indies.

To determine the correlation of ultrasonographic estimation of fetal weight and actual birthweight and the impact of the level of resident's training on the results. A prospective study of 90 women with term pregnancies. Ultrasound estimated fetal weight (EFW) was calculated by a preprogrammed Hadlock formula. Days from ultrasound to delivery were less than seven. The EFW was compared to the actual birthweight at delivery. The year of training of the resident that performed the ultrasound was recorded. Exclusion criteria included Diabetes mellitus and known fetal anomalies. Mean age was 28 years, parity zero to four, mean gestational age 38 weeks. There was an average over-estimation of 64.8 grams. The difference between mean EFW and mean BWT was not significant (p = 0.067). The difference between mean EFW and mean BWT when calculated according to year of residency was not significant, p = 0.075 and 0.402 for junior and senior residents, respectively. There is good correlation between resident's ultrasonographic estimation of fetal weight and actual birthweight at the UHWI. There was no significant difference in correlation between senior and junior residents. Development in computer technology might contribute to decrease in the learning curve.

PFM.20 A study on the accuracy and validity of ultrasonographic fetal weight estimation in a mainly non-Caucasian population

IntroductionTo evaluate the accuracy and validity of common formulae for estimating fetal weights using ultrasonographic measurements in low birthweight babies (LBW) ≤2500 g and high birth weight (HBW) ≥4000 g.MethodsAll...

The accuracy of ultrasound-estimated fetal weight in extremely preterm infants: a comparison of small for gestational age and appropriate for gestational age

To compare the accuracy of estimated fetal weight (EFW) in extremely preterm small for gestational age (SGA) and appropriate for gestational age (AGA) infants and report other significant factors influencing the accuracy of EFW. A retrospective cohort study of singleton pregnancies 22(+0) -27(+6) weeks. Women were included in the study if an ultrasound scan had been performed within seven days of delivery, with no major fetal anomaly and data available to calculate customised birthweight (BW) centiles. Mean error of EFW and actual BW and mean % error of EFW and actual birthweight were compared for SGA and AGA infants. A stepwise backward elimination linear regression model was used to determine the significant factors influencing the accuracy of EFW. A total of 134 cases (51 SGA and 83 AGA) were analysed. The mean gestational age at delivery was 25(+2) weeks (SD 11.5days) and mean BW 711g (SD 227g). Overall mean percentage error of EFW and actual BW was 8.8% (range 0-34.6%). There was a significant difference in mean error of EFW and actual BW for SGA and AGA deliveries (mean +16g versus -23g, respectively, P=0.01) and in mean % error of EFW (11.2%, 95%CI 9.1-13.3 versus 7.4%, 95% CI 6.2-8.6 P=0.009). Factors that significantly influenced the accuracy of EFW included SGA (P=0.001, coeff.=-3.73, 95% CI -5.94/-1.52), scan to delivery interval (P=0.02, coeff.=0.66, 95% CI 0.12/1.21) and reduced amniotic fluid (P=0.008, coeff=3.61, 95% CI -5.47/-0.85). Ultrasonographic EFW for extreme preterm SGA fetuses is less accurate than AGA fetuses and is more likely to overestimate EFW. This should be considered when counselling women with growth restricted fetuses at the limits of viability.

The effect of severe maternal obesity on the accuracy of ultrasonographic fetal weight estimation: a prospective cohort study

ObjectivesTo assess the accuracy of fetal biometry measurements in predicting birthweight and to compare serial fetal biometry measurements in women with very severe obesity and lean controls.Methods174 very severely obese...

The Effect of Breech Presentation on the Accuracy of Estimated Fetal Weight

To determine whether fetal presentation affects the accuracy of ultrasonographic estimated fetal weight (EFW). This is a retrospective cohort study of singleton pregnancies that underwent ultrasonographic EFW within 3 weeks of delivery at a single institution from 1993 to 2008. Breech presenting fetuses were compared with those presenting cephalic. EFW using the Hadlock formula was compared with actual birth weight (ABW) and reported as mean difference and mean percentage difference. Differences were also considered categorically. Subgroup analyses were performed of women who delivered within 4 days of scan and excluding women with comorbidities. Ability to detect small and large for gestational age infants was compared. Evaluation of 3770 patients, 183 (4.9%) breech presenting and 3587 (95.1%) cephalic presenting revealed no difference in mean gram difference (-222.1 g ± 312.6 vs. -210.7 g ± 793.2, p = 0.084), respectively, or ability to accurately predict within 10% of ABW (adjusted odds ratio [AOR] 1.23; 95% CI, 0.89,1.69; p = 0.208). Subgroup analyses revealed similar results. There was no difference in the ability to detect small and large for gestational age infants. Presentation does not demonstrably affect the accuracy of ultrasonographic EFW when utilizing the Hadlock formula.

OP13.15: Evaluation of clinical performance of obstetric residents: ultrasonographic estimation of fetal weight

OP13.15: Evaluation of clinical performance of obstetric residents: ultrasonographic estimation of fetal weight

Ultrasonographic fetal weight estimation: accuracy of formulas and accuracy of examiners by birth weight from 500 to 5000 g.

To determine the accuracy of birth weight in different birth weight (BW) groups using widely accepted formulas for fetal weight estimation (EFW). The secondary purpose was to estimate the role of examiners on the accuracy of EFW. The cross-sectional data were obtained from 5612 pregnant women. Fetal weight was estimated for each fetus using the formulas of Campbell and Wilkin, Shepard, 2 formulas of Hadlock and Merz. Inclusion criteria were: singleton pregnancy, complete ultrasound parameters, EFW obtained within the last week prior to delivery, the live born infant without congenital malformations or hydrops. The highest intraclass correlation coefficient and the most stable results in all BW groups were generated with both Hadlock formulas. Both Hadlock and Campbell formulas had the lowest percent errors (PE) in BW groups between <1500 g and 3500 g. Shepard and Merz formulas had lower PEs in BW groups between 3501 g and >4000 g. However in BW groups under 3500 g they were imprecise. The PE of EFW varied from -4.0 +/- 8.5% to 1.3 +/- 8.5% between examiners. Both Hadlock formulas showed the most stable results in all of the weight groups. There is also a need for routine evaluation of the accuracy of EFW for every examiner, to make suggestions, what fetal measurements must be improved to improve EFW.

Accuracy of sonographic estimation of fetal weight before induction of labor in diabetic pregnancies and pregnancies with suspected fetal macrosomia.

To evaluate the accuracy of sonographic estimation of fetal weight (EFW) in diabetic pregnancies and pregnancies with suspected fetal macrosomia. 63 women with diabetic pregnancies, 74 nondiabetic women with suspected large-for-gestational-age (LGA) infants, and 161 controls underwent ultrasound assessment prior to induction of labor. EFW was compared to the weight at birth, 1-3 days later. EFW was highly correlated to birth weight. Absolute or actual weight differences between the birth weight and the EFW, and the rate of EFW within 10% of birth weight were not different between the groups. A linear regression model controlling for maternal and gestational age, diagnosis of gestational or pregestational diabetes, birth weight, gravidity, parity, nulliparity, placental location and AFI was not significantly correlated to the absolute or actual weight differences. In pregnancies with suspected LGA, higher birth weight was an independent and significant predictor of high weight difference inaccuracy. The ultrasonographic EFW 1-3 days before delivery is highly correlated with birth weight, reaffirming the clinical use of abdominal circumference and femur length in estimating fetal weight near labor at term. In pregnancies with suspected LGA fetuses and higher prevalence of macrosomia, ultrasound has higher sensitivity but lower specificity than the controls.