(Ultrasound Review) According to researchers from the University of California, San Francisco, the growth between two ultrasound examinations can be used to predict neonatal outcome, even when gestational age is unknown. Because of normal variation in fetal size and the possibility of incorrect menstrual age, an alternative method to a single biometrical assessment was investigated. The authors hypothesized this should more accurately determine whether a fetus was pathologically small.
Published in Radiology, the study included 321 women with a singleton pregnancy that had two or more ultrasound examinations during the second and third trimesters. Measurements of the femur length, bipareital diameter and abdominal circumference were used to estimate fetal weight. In order to determine a normal distribution of fetal growth, they analyzed the estimated fetal weight data from 1,687 fetuses with known gestational age. Ideally the initial ultrasound examination should be performed after 20 weeks’ gestational age, as the authors believed this represented the first clinically relevant period. All ultrasound examinations were performed 2-17 weeks apart.
Results of the study determined that "inadequate fetal growth was associated with 3.9 times the risk of a birth weight less than 2500g, 17.7 times the risk of a birth weight less than the 3rd percentile for gestational age.’ Also, there was "2.3 the risk of preterm birth, 2.6 times the risk of a long newborn hospital stay, and 3.6 times the risk of neonatal intensive care unit admission."
It was revealed that inadequate fetal growth was better at identifying more fetuses with poor birth outcomes than a single estimated fetal weight that was lower than normal.
"Even the fetuses with an average weight were at an increased risk for poor outcomes if they demonstrated inadequate growth, they reported. Fetuses that were large for dates showed periods of slowed growth, but this had no deleterious effect on outcome, probably because they had already reached an adequate size. The authors concluded that "morbidity is significantly increased among fetuses who demonstrate less than expected growth."
"US evaluation of fetal growth: prediction of neonatal outcomes"R Smith-Bindman et al
Dept of radiology, University of California, San Francisco UCSF/Mt Zion Medical Center, San Francisco, CA
Radiology 2002 April; 223:153-161
By Ultrasound Review
May 29, 2002
Copyright © 2002 AuntMinnie.com
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&fit=crop&h=100&q=70&w=100)
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnie.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
