scholarly journals Early Fetal Weight Estimation with Expectation Maximization Algorithm

2018 ◽  
Author(s):  
Loc Nguyen ◽  
Thu-Hang T. Ho
Keyword(s):  
Expectation Maximization ◽  
Missing Values ◽  
Expectation Maximization Algorithm ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Weight Estimation ◽  
Time Points ◽  
Fetal Weight Estimation ◽  
Gestational Period ◽  
Dual Regression

Fetal weight estimation before delivery is important in obstetrics, which assists doctors diagnose abnormal or diseased cases. Linear regression based on ultrasound measures such as bi-parietal diameter (bpd), head circumference (hc), abdominal circumference (ac), and fetal length (fl) is common statistical method for weight estimation but the regression model requires that time points of collecting such measures must not be too far from last ultrasound scans. Therefore this research proposes a method of early weight estimation based on expectation maximization (EM) algorithm so that ultrasound measures can be taken at any time points in gestational period. In other words, gestational sample can lack some or many fetus weights, which gives facilities to practitioners because practitioners need not concern fetus weights when taking ultrasound examinations. The proposed method is called dual regression expectation maximization (DREM) algorithm. Experimental results indicate that accuracy of DREM decreases insignificantly when completion of ultrasound sample decreases significantly. So it is proved that DREM withstands missing values in incomplete sample or sparse sample.

scholarly journals Accuracy of ultrasonic fetal weight estimation using head and abdominal circumference and femur length

2005 ◽  
Vol 58 (11-12) ◽  
pp. 548-552 ◽  
Author(s):  
Ljiljana Mladenovic-Segedi ◽  
Dimitrije Segedi
Keyword(s):  
Birth Weight ◽  
Head Circumference ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Weight Estimation ◽  
Fetal Head ◽  
Total Body Mass ◽  
Femur Length ◽  
Fetal Weight Estimation ◽  
Gynecology And Obstetrics

Introduction Former investigations have shown that the accuracy of fetal weight estimation is significantly higher if several ultrasonic fe?tal parameters are measured, because the total body mass depends on the size of fetal head, abdominal circumference and femur length. The aim of this investigation was to establish the best regression model, that is a number of combinations of fetal parameters providing the most accurate fetal weight estimation in utero in our population. Material and methods This prospective study was carried out at the Gynecology and Obstetrics Clinic of the Clinical Center Novi Sad. It included 270 pregnant women with singleton pregnancies within 72 hours of delivery who underwent ultrasound measurements of the biparietal diameter (BPD), head circumference (HC), ab?dominal circumference (AC) and femur length (FL). Results In regard to fetal weight estimation formulas, the deviation was lowest using regression models that simultaneously analyzed four fetal parameters (0.55%) with SD ?7.61%. In these models the estimates of fetal weights were within ?5% of actual birth weight in 48.89%, and within ?10% of actual birth weight in 81.48%. Good results were also obtained using AC, FL measurements (0.92% ? 8.20) as well as using AC, HC, FL measurements (-1.45% ? 7.81). In our sample the combination of AC and FL model gave better results in fetal weight estimation (0.92 ? 8.20%) than the one using BPD and AC (2.97 ? 8.83%). Furthermore, the model using parameters AC, HC and FL showed a lower error in accuracy (-1.45 ? 7.81%) than the model using BPD, AC and FL (2.51 ? 7.82%). Conclusion This investigation has confirmed that the accuracy of fetal weight estimation increases with the number of measured ultra?sonic fetal parameters. In our population the greatest accuracy was obtained using BPD, HC, AC and FL model. In cases when fast estimation of fetal weight is needed, AC, HC, FL model may be appropriate, but if fetal head circumference cannot be measured (amnion rupture and/or fetal head already in the pelvis) the AC, FL model should be used.

scholarly journals INTEGRATION OF FETAL MID THIGH SOFT TISSUE THICKNESS IN ULTRASOUND BIRTH WEIGHT ESTIMATION FORMULA INCREASES THE ACCURACY OF FETAL WEIGHT ESTIMATION NEAR TERM

2018 ◽  
Vol 11 (4) ◽  
pp. 446
Author(s):  
Shripad Hebbar ◽  
Sukriti Malaviya ◽  
Sunanda Bharatnur
Keyword(s):  
Birth Weight ◽  
Prediction Models ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Estimation Methods ◽  
Weight Estimation ◽  
Singleton Pregnancy ◽  
Fetal Biometry ◽  
Fetal Weight Estimation ◽  
Soft Tissue Thickness

Objective: The objective of the study was to find whether incorporation of MTSTT in fetal weight estimation formulae which are traditionally based on biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) improves birth weight (BW) estimation. Methods: In a prospective observational study, MTSTT was measured within 1 week of delivery in 100 women with term singleton pregnancy along with other standard biometric parameters, i.e. BPD, HC, AC and FL, and MTSTT. Multiple regression analysis was carried out using PHOEBE regression software using different combinations of biometric variables to find out the best fit model of fetal weight estimation. The predicted BW was compared with actual neonatal BW soon after delivery and regression coefficients (R2) were determined for each of prediction models for comparing the accuracies. Results: Mean gestational age at delivery was 38.4±1.08 weeks and the BW of neonates varied between 2.18 kg and 4.38 kg (mean ± standard deviation: 3.07±0.43 kg). By adding MTSTT to BPD, HC, AC, and FL, we obtained the formula Log 10 (BW) = −0.14783+0.00725 *BPD +0.00043 *HC +0.00436 *AC +0.01942 *FL +0.16299 *MTSTT, which had a very good Pearson regression coefficient ((r2: 0.89 p<0.001) compared to conventional models based on standard fetal biometry. All prediction models had better strength of correlation when combined with MTSTT (p<0.001). The routine four parameter formula could identify 45% and 80% of fetuses within 5% and 10% weight range; pick up rate was further increased to 61% and 95% by addition of MTSTT. Conclusion: It is evident that addition of MTSTT to other biometric variables in models of fetal weight estimation improves neonatal BW prediction (r2=0.89).

scholarly journals Deviasi Taksiran Berat Janin pada Metode Johnson-Toshack, Formula Sederhana dan Formula Dare

2017 ◽  
Vol 8 (2) ◽  
pp. 235
Author(s):  
Emy Rianti ◽  
Siti Aminah
Keyword(s):  
Birth Weight ◽  
Simple Formula ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Weight Estimation ◽  
Cross Sectional ◽  
Birth Canal ◽  
Fetal Weight Estimation ◽  
Method Of Measurement ◽  
Infant Birth

<p><em>The ability of the birth attendant to estimate the birth weight of the fetus </em><em>is </em><em>very</em><em> important that it does not cause </em><em>childbirth</em><em> dystocia that may cause </em><em>rip</em><em> in the birth canal. </em><em>The aim of this study was to</em><em> compare the deviation of fetal weight estimation according to Johnson-Toshack method, simple formula and Dare formula. Thedesign used was cross sectional, </em><em>the data taken primarily</em><em>, involving 100 respondents at Fatmawati General Hospital Jakarta, from August to September 2015. The findings showed that the smallest deviation mean of fetal weight estimation is Johnson-Toshack method. The results of this method of measurement tend to be close to infant birth weight, especially in the client </em><em>childbirth</em><em> with abdominal circumference 90 - 100 cm. The conclusion of this study is that Johnson-Toshack's fetal weighing estimates are more appropriate for </em><em>childbirth</em><em> with 90 to 100 cm </em><em>a</em><em>bdominal circumference size, except in </em><em>childbirth</em><em> with ruptured membranes, applying a fetal weight estimate based on the Dare formula would be more appropriate.</em></p><p><strong><em> </em></strong></p>

scholarly journals Validation of Sonographic Fetal Weight Estimators Among Term Parturients in Uganda

2020 ◽  
Author(s):  
Senai Goitom Sereke ◽  
Richard Okello Omara ◽  
Felix Bongomin ◽  
Sarah Nakubulwa ◽  
Harriet Nalubega Kisembo
Keyword(s):  
Birth Weight ◽  
Mode Of Delivery ◽  
Mean Difference ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Weight Estimation ◽  
Fetal Weight Estimation ◽  
Biparietal Diameter ◽  
Mulago National Referral Hospital ◽  
Fetal Birth Weight

Abstract BackgroundAccuracy of fetal weight estimation by ultrasound is essential in making decisions on the time and mode of delivery. There are many proposed formulas for fetal weight estimation such as Hadlock 1, Hadlock 2, Hadlock 3, Hadlock 4 and Shepard. What best applies to the Ugandan population isn’t known since no validation of any of the formulas has been done before. The primary aim of this study was to determine the accuracy of sonographic estimation of fetal weight using five most commonly used formulas, and analyze formula variations for different weight ranges. MethodsThis was a hospital based prospective cohort study at Mulago National Referral Hospital, Kampala, Uganda. A total of 356 pregnant women who consented and were within three days of birth, prenatal ultrasound fetal weight determined by measuring the biparietal diameter, head circumference, abdominal circumference, femoral length, and then was compared with actual birth weight. ResultsThe overall accuracy of Hadlock 1, Hadlock 2, Hadlock 3, Hadlock 4 and Shepard formula were 66.9%, 73.3%, 77.3%, 78.4% and 69.7% respectively. All Hadlocks showed significant mean difference between weight estimates and actual birth weight (p<0.01) whereas Shepard formula did not [p - 0.2], when no stratification of fetal weights was done. However, all Hadlocks showed a none significant (p-values > 0.05) mean difference between weight estimates and actual birth weight when the actual birth weight was ≥4000.0gms. Shepard weight estimates showed a none significant mean difference when actual birth weight was <4000gms. Bland-Altman graphs also showed a better agreement of weight estimated by Shepard formula and actual birth weights. ConclusionAll the five formulas were accurate at estimating actual birth weights within 10% accuracy. However, this accuracy varied with the fetal birth weight. Shepard was more accurate in estimating actual birth weights <4000grams whereas all Hadlocks were more accurate when the actual birthweight was ≥ 4000grams.

scholarly journals Prospective verification of sonographic fetal weight estimators among term parturients in Uganda

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Senai Goitom Sereke ◽  
Richard Okello Omara ◽  
Felix Bongomin ◽  
Sarah Nakubulwa ◽  
Harriet Nalubega Kisembo
Keyword(s):  
Birth Weight ◽  
Mode Of Delivery ◽  
Mean Difference ◽  
Fetal Weight ◽  
Abdominal Circumference ◽  
Weight Estimation ◽  
Fetal Weight Estimation ◽  
Biparietal Diameter ◽  
Mulago National Referral Hospital ◽  
Fetal Birth Weight

Abstract Background Accuracy of fetal weight estimation by ultrasound is essential in making decisions on the time and mode of delivery. There are many proposed formulas for fetal weight estimation such as Hadlock 1, Hadlock 2, Hadlock 3, Hadlock 4 and Shepard. What best applies to the Ugandan population is not known since no verification of any of the formulas has been done before. The primary aim of this study was to determine the accuracy of sonographic estimation of fetal weight using five most commonly used formulas, and analyze formula variations for different weight ranges. Methods This was a hospital based prospective cohort study at Mulago National Referral Hospital, Kampala, Uganda. A total of 356 pregnant women who consented and were within 3 days of birth were enrolled. Prenatal ultrasound fetal weight determined by measuring the biparietal diameter, head circumference, abdominal circumference, femoral length, and then was compared with actual birth weight. Results The overall accuracy of Hadlock 1, Hadlock 2, Hadlock 3, Hadlock 4 and Shepard formula were 66.9, 73.3, 77.3, 78.4 and 69.7% respectively. All Hadlocks showed significant mean difference between weight estimates and actual birth weight (p < 0.01) whereas Shepard formula did not [p - 0.2], when no stratification of fetal weights was done. However, all Hadlocks showed a none significant (p-values > 0.05) mean difference between weight estimates and actual birth weight when the actual birth weight was ≥4000.0 g. Shepard weight estimates showed a none significant mean difference when actual birth weight was < 4000 g. Bland-Altman graphs also showed a better agreement of weight estimated by Shepard formula and actual birth weights. Conclusion All the five formulas were accurate at estimating actual birth weights within 10% accuracy. However, this accuracy varied with the fetal birth weight. Shepard was more accurate in estimating actual birth weights < 4000 g whereas all Hadlocks were more accurate when the actual birthweight was ≥4000 g.

Macrosomia – a new formula for optimized fetal weight estimation

2008 ◽  
Vol 68 (S 01) ◽  
Author(s):  
NC Hart ◽  
J Siemer ◽  
B Meurer ◽  
TW Goecke ◽  
RL Schild
Keyword(s):  
Fetal Weight ◽  
Weight Estimation ◽  
Fetal Weight Estimation ◽  
New Formula
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