Accuracy of ultrasound in estimating fetal weight in New Zealand

Autor: Joanne Kelly, Colleen J. Bergin, Sarah Benson‐Cooper, Gregory P. Tarr
Rok vydání: 2021
Předmět:
Zdroj: Australas J Ultrasound Med
ISSN: 2205-0140
Popis: INTRODUCTION: Ultrasound estimation of fetal weight is an important factor guiding antenatal management. We aimed to review the accuracy of ultrasound in predicting fetal weight and birthweight category and identify influencing factors. METHODS: We performed a retrospective study of term pregnant women who underwent ultrasound within 7 days of delivery at National Women's Health between January 2019 and January 2020. Stillbirths, major fetal anomalies and multiple pregnancies were excluded. Estimated fetal weight (EFW) was calculated using Hadlock formula and compared with birthweights. We evaluated change in weight categories due to these errors. RESULTS: Of 560 fetuses included, three quarters (n = 425, 76%) of EFWs were within 10% of birthweight. 135 fetuses had EFWs either less than 90% (n = 19) or greater than 110% (n = 116). Fetuses with EFW 110% were associated with higher EFW, later gestational age and older maternal age. US incorrectly estimated 71 (12.7%) fetal birthweight categories. Underestimated weight category (8.9%) was associated with higher maternal BMI. DISCUSSION: Inaccurate EFWs were more common at the extremes of fetal weight. A significant association was underestimation birthweight in mothers with increased BMI, who are at increased risk for perinatal and surgical complications. CONCLUSION: Our accuracy of 76% correctly predicted EFWs compares favourably with previous studies. Clinicians and sonographers should be aware of the increased risk for inaccurate categorisation of fetuses at the extremes of EFW and in mothers with increased BMI.
Databáze: OpenAIRE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje