OC08.06: Accuracy and precision of crown–rump length and other fetal biometry in nuchal translucency screening interpretation
Year: 2011
Type: conference-abstract
Abstract: In first trimester risk assessment, crown–rump length has been utilized as the gold standard for dating pregnancies and interpreting screening results. Other fetal biometric measurements have been employed to confirm gestational age, but not to interpret screening results. The purpose of this study is the compare the accuracy and precision of crown–rump length and other fetal biometric measurements in the interpretation of first trimester nuchal translucency. The goal is to determine which measurement leads to the least variability when an observed nuchal translucency measurement is related to the expected level for the observed biometry value (MoMs). Women presenting to an academic fetal diagnostic center between 11 + 0 and 13 + 6 weeks were examined by one sonographer followed by one physician. Each examiner obtained 3 independent measurements of fetal biometric parameters, and NT. Patients were excluded for fetal malformations or demise. Biometry-specific expected NT values were calculated using regression models, and the results were converted into MoMs. The standard deviation of log MoM was compared, and the smallest value was regarded as reflecting the biometric measure with the greatest accuracy and precision. Measurements were obtained on 135 fetuses. Abdominal circumference yielded MoMs with the smallest standard deviation, significantly lower than for CRL, the next smallest (P < 0.0001). The standard deviation of AC remained the smallest when results from sonographers and physicians were considered separately, and when the mean of the three exams was used rather than the individual exam results. Abdominal circumference is the most accurate and precise biometric measurement for the interpretation of nuchal translucency screening results. Since crown rump length is currently utilized to calculate NT MoMs in order to place fetuses in categories of risk for aneuploidy, consideration should be given to an alternative model for calculation of NT MoMs using other fetal biometric measurements.
DOI: 10.1002/uog.9138
Authors: R. Gutkin, H. Cuckle, N. Silverman, D. Krakow, K. Patel, L. D. Platt
Language: English
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W1502440963