Accuracy Of Birth Weight Prediction Research Articles

Third trimester ultrasound for fetal macrosomia: optimal timing and institutional specific accuracy

Purpose: To determine the performance of third trimester ultrasound in women with suspected fetal macrosomia.Materials and methods: We performed a retrospective cohort study of fetal ultrasounds from January 2004 to December 2014 with estimated fetal weight (EFW) between 4000 and 5000 g. We determined accuracy of birth weight prediction for ultrasound performed at less than and greater than 38 weeks, accounting for diabetic status and time between ultrasound and delivery.Results: There were 405 ultrasounds evaluated. One hundred and twelve (27.7%) were performed at less than 38 weeks, 293 (72.3%) at greater than 38 weeks, and 91 (22.5%) were performed in diabetics. Sonographic identification of EFW over 4000 g at less than 38 weeks was associated with higher correlation between EFW and birth weight than ultrasound performed after 38 weeks (71.5 versus 259.4 g, p < .024). EFW to birth weight correlation was within 1.7% of birth weight for ultrasound performed less than 38 weeks and within 6.5% of birth weight for ultrasound performed at greater than 38 weeks.Conclusions: Identification of EFW with ultrasound performed less than 38 weeks has greater reliability of predicting fetal macrosomia at birth than measurements performed later in gestation. EFW to birth weight correlation was more accurate than previous reports.

Predictability of offspring birth weight using simple parental anthropometrics in a government hospital in Lagos, Nigeria

Background : Birth weight is of interest to quantitative geneticists and to obstetricians being one of the most important complex traits that determine perinatal outcome. Moreover, It is a predictor of mother’s and baby’s health later in life. Accuracy of prediction of baby’s birth weight is therefore central to perinatal success and the quality of life of the baby in adulthood. Current intrauterine procedures including ultrasonography are of inadequate predictive values. The possibility of combining parental anthropometric data with already existing predictive methods such as ultrasonography may increase accuracy of birth weight prediction for better peri- and postnatal management of low or high birth weight. Aim : The aim is to determine the parental anthropometric predictors of baby’s birth weight in Lagos, Nigeria. Using parental explanatory variables to predict baby’s weight could complement the already existing predictive methods such as ultrasonography for more accurate prediction of birth weight. Methods and Materials : Parental parameters such as weight, height, BMI and other anthropometric attributes were obtained from 250 couples. Baby’s birth weight was taken immediately after birth. Results : Only three parental factors were needed to substantially predict offspring birth weight. These include mid-paternal weight which was the most explanatory variable, followed by parity, and then maternal weight. Conclusion : Complementing ultrasonographic and other data with information from parental variables, especially mid-paternal weight, parity and maternal weight might improve accuracy of prediction of low birth weight or macrosomic babies and therefore a reduction in perinatal failure. Keywords : Birth weight, anthropometrics, macrosomia, predictability, Nigeria

275: Does gestational age affect the accuracy of birth weight prediction when using the gestation-adjusted projection method?

The gestation adjusted projection (GAP) method has been shown to be a reliable predictor of birth weight in gestational diabetes (GDM). The purpose of this study was to determine the ideal gestational age at which to apply this method.

Accuracy of birthweight prediction through adjustment for individual maternal and pregnancy characteristics

ObjectiveWhile customised centiles bundle a set of physiological characteristics together to adjust the standard for birthweight and growth potential, the authors wanted to investigate the role which individual variables have...

Estimativa de peso ao nascimento utilizando a ultrassonografia bidimensional e tridimensional

Assess and compare accuracy of birth weight prediction using a combination of two-dimensional (abdominal circumference - AC and femur length - FL) and three-dimensional parameters (fetal arm -VolArm and thigh -VolTh volumes). A cross sectional study was carried out involving 78 singleton, live, euploid fetuses without structural malformations born within 48 hours after ultrasonography. VolArm and VolTh were obtained by three-dimensional ultrasound using the multiplanar mode at 5 mm intervals. AC and FL were measured by two-dimensional ultrasound. Linear and polynomial regressions were calculated to determine the best formula to predict birth weight using VolArm, VolTh , CA and FL. ANOVA was used to compare errors in birth weight prediction using this formula and those obtained using the Shepard and Hadlock formulae. The best formula for prediction of birth weight was a simple linear regression (Weight = -1486.1 + 60.5AC + 140.57FL + 16.6VolArm + 4.8VolTh), R2= 0.932. The error (E), absolute error (AE), percent error (PE) and absolute percent error (APE) for this new formula were 0 g, 0.2%, 112.2 g and 3.7%. This new formula had smaller E, AE, PE and APE than the Shepard formula and smaller AE and APE than Hadlock s formula. A formula using VolArm, VolTh, AC and FL was more accurate for prediction of birth weight than formulae using only two-dimensional parameters.

Ultrasound Prediction of Fetal Macrosomia in Diabetic Women and its Effect on the Route of Delivery and the Outcome of Pregnancy

Objective: The purpose of this study is to review the maternal and neonatal outcome in pregnant diabetic women given a trial of labor and delivered macrosomic infants (&gt;4000 grams) and to assess the accuracy of birth weight prediction by ultrasound examination at term. Methods: One hundred and twenty-nine charts of pregnant diabetic women were reviewed, sixty eight women were given a trial of labor and delivered macrosomic fetuses (&gt;4000 grams), fifty of them had vaginal delivery and the other eighteen had caesarean delivery. In the other group, 61 patients delivered by elective caesarean section, for 41 of them the indication was fetal macrosomia (&gt;4000 grams) as estimated by ultrasound examination and in the other 20, it was due to clinical estimation of big baby. Maternal and neonatal complications were reviewed in each group. Maternal complications included lacerations, hemorrhage and infection and the neonatal complications evaluated were shoulder dystocia and associated birth trauma, asphyxia, and mortality. The accuracy of ultrasound in estimating fetal weight was also evaluated. Results: Sixty eight (52.7%) women attempted a trial of labor; 73.5% delivered vaginally and 26.5% had a caesarean delivery. All, except two, had macrosomic fetuses (&gt;4000 grams). Only one woman, of those who delivered vaginally, had postpartum hemorrhage due to atonic uterus. The incidence of shoulder dystocia for infants weighing 4000-4499 grams was 6.3% and those infants had the same incidence (6.3%) of brachial plexus injury. There was no perinatal asphyxia or perinatal mortality among those infants who were delivered vaginally. There were no maternal complications for women who had caesarean delivery after labor (18 patients) but there was perinatal asphyxia in two infants who were treated properly without any neurological sequele. Elective caesarean delivery was performed in 47.3% of the study population. There were no neonatal complications or perinatal mortality in this group of patients and only one woman had wound infection. The sonographic prediction of fetal weight was accurate in 52.4% of the cases. The over estimation was in 50.8% of the estimated fetal weights and 49.2% of them were underestimated when compared to actual birth weights. Conclusions: Caution should be taken in the use of sonographic estimations of fetal weight to guide obstetric decisions concerning labor and delivery. Special consideration should be given to diabetic patients having fetuses with estimatedfetal weights between 4000 and 4500 grams. Flexibility in the management of these patients is best, taking in consideration their previous obstetric performance and if the estimated fetal weight is closer to 4500grams than to 4000 grams, it is perhaps, better to proceed to a primary caesarean delivery.

Prediction of birth weight by ultrasound-estimated fetal weight: a comparison between single and repeated estimates

Ultrasound estimation of fetal weight is used for diagnosing intrauterine growth retardation. The aim of the present study was to assess the accuracy of birth weight prediction by use of a single or repeated estimations of fetal weight in the third trimester. 1000 pregnant women considered at risk were scheduled to ultrasound estimation of fetal weight, using Warsof's formula, at 28, 31, 34 and 37 weeks of gestation. The 421 pregnancies with term delivery and complete set of ultrasound examinations and 57 pregnancies with preterm delivery with ultrasound examination at 16 and 28 weeks and once more before delivery were included in the present analysis. The accuracy of birth weight prediction improved significantly for every three weeks from 28 to 37 weeks of gestation in the term infants. Prediction based on the average of repeated weight estimates or linear extrapolation from two estimates or extrapolation by a second order polynomium fitted to four estimates did not improve accuracy compared to prediction based on the last estimate before delivery. When more than one ultrasound estimation of fetal weight are available, prediction of birth weight in relation to gestational age should be based on the last ultrasound examination only.