Accuracy of sonographic fetal weight estimation in a tertiary care hospital in Bharatpur, Nepal

Abstract

Background & Objectives: Among the var ious methods used in the estimation of intrauterine fetal weight, sonographic fetal weight estimation is the one and has become an important component of antenatal care. The study was conducted with objective to assess the accuracy and reliability of ultrasound estimation of fetal weight in women with a singleton term pregnancy. Materials & Methods: This was a prospective cross-sectional study of 120 women with singleton term pregnancies. Ultrasound estimated fetal weight was calculated by measuring the biparietal diameter and abdominal circumference. The estimated fetal weight was compared to the actual birth weight post delivery. The correlation between estimated fetal weight and actual birth weight was assessed by Pearson's correlation coefficient and the accuracy of sonographic fetal weight estimation was measured using mean error, mean absolute error, mean percentage error, mean absolute percentage error and proportion of estimates within 10% of actual birth weight. Results were tested at error level set at p ≤ 0.05. Results: Mean estimated and actual birth weights were 2863.5 ± 441.9 g and 2822.5 ± 407.7 g respectively. There was a strong positive correlation between estimated fetal weight and actual birth weight (r= 0.71, p <0.001). The mean percentage error and mean absolute percentage error of ultrasound fetal weight estimations were 1.9 ± 11.4% and 8.8 ± 7.5% respectively. Conclusion: Sonogr aphically estimated fetal weight had str ong positive correlation with actual birth weight and thus sonography can be used in the estimation of fetal weight for the better perinatal outcome. Key words: Actual bir th weight; Ultr asonogr aphically estimated fetal weight Citation: Pr asad VN, Poudel P, Chhetr y PK. Accur acy of sonogr aphic fetal weight estimation in a tertiary care hospital in Bharatpur, Nepal. JCMS Nepal. 2016;12(4):174-8. 175 weight estimation algorithm in College of Medical Sciences, Bharatpur. MATERIALS AND METHODSThis was a prospective cross-sectional study conducted during the period January 2015 to January 2016 at College of Medical SciencesTeaching Hospital (COMS TH), Bharatpur. The study included 120 normal antenatal women at term pregnancy (37 to 42 weeks of gestation) who were assessed clinically at the department of obstetrics and gynaecology and referred to the radiology department for ultrasonography. Informed consent of the patient and approval from the ethical committee of the institution was obtained prior to the procedure. The exclusion criteria were multiple pregnancy, IUGR (Intrauterine Growth Retardation), stillbirth, congenital fetal malformations, hydrops fetalis, diabetes mellitus in mother and delivery after seven days of ultrasonic fetal weight estimation. Ultrasonography of each case included in the study was done using Samsung Medison ACCUVIX A30 ultrasound equipment with a scanner frequency of 3.5 MHz to assess fetal viability, fetal presentation, biparietal diameter, head circumference, abdominal circumference, femur l...

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

“…This implies that when it is indicated, ultrasound should be used to estimate the fetal weight for the purposes of planning delivery and monitoring of the fetus. Similar findings have been observed by other studies [2, 6, 12].…”

“…The absolute mean error of estimation of 258.52 recorded in our study is comparable to observed values by Prasad et al in Nepal [12]. The mean absolute percentage of 7.56% is comparable to 8.76%, 7.2%, 7.7% reported by Prasad et al [12], Lafont et al [13], Colman et al [14], and Houzé de l'Aulnoit et al [15], respectively. It is also within the 6–12% reported in the literature [4].…”

“…The mean birth weight of 3.47 kg is comparable to values from Lagos, Nigeria [10] but higher than values from Nepal [12] and Bangladesh [2]. The differences could be linked to the gestational age at scanning and the genetic and racial variations.…”

Accuracy and reliability of ultrasound estimation of fetal weight in women with a singleton term pregnancy

“…These results are comparable with mean percentage error and mean absolute percentage error of ultrasound fetal weight estimations were 1.9±11.4% and 8.8±7.5% respectively in the study done by Prasad et al 15 These results are also consistent with previously observed findings that the mean absolute percentage error of predicting birth weight varies from 6% to 12% of actual birth weight. 12 The percentage of estimates within ±10% of the actual birth weight was found to be 67.3% which is comparable with the percentage of estimates within ±10% of the actual birth weight was found to be 65% in the study done by Prasad et al 15 These results are also consistent with what have been previously observed that 40-76% of the estimates were within 10% of actual birth weight. 12 The ultrasound estimated fetal weight (EFW) had a strong positive correlation with actual birth weight (ABW) of the newborns (r = 0.58, p <0.001).…”

Study on the Application of GE-E10 Ultrasound Equipment to Estimate Fetus Weight and Compare Its Accuracy With Birth Weight

“…Macrosomia refers to the weight of a newborn being more than 4000g within one hour after birth. The prenatal diagnosis of macrosomia will provide guidance for medical staff to make correct treatment during delivery, thus reducing the incidence of maternal and infant obstetric complications [9]. In addition, the accurate estimation of a fetus whose birth weight is less than 2500g is also conducive to early prenatal diagnosis of intrauterine growth retardation and improvement of maternal and infant pregnancy outcomes [10].…”