Estimation of birthweight by measurement of fetal thigh soft‐tissue thickness improves the detection of macrosomic fetuses

Abstract

The accuracy of sonographic estimation of birthweight in suspected macrosomic fetuses is compromised by the imprecision of the biometrical measurements. This prospective study evaluated the performance of an equation based on linear measurement of the soft tissue above the external side of the fetal femur. The performance of this algorithm was compared with two classical algorithms. Sonographic measurements were taken within 48 h before of delivery. Sixty-two patients with fetuses with suspected macrosomia were enrolled. The studied formulas were compared between them and showed a significant correlation with birthweight (p < 0.0001) and satisfactory statistical performances (r > 0.9). The new formula showed a reduced standard deviation that means a lower internal error in the prediction. This study supports the potential of this new approach for the estimation of birthweight in large fetuses based on sonographic linear measurements only.

Estimation of Fetal Weight during Labor: Still a Challenge

“…Moreover, it includes a measurement of soft tissue, thought to be of great value to evaluate fetal growth deviations as it involves adipose tissue plus lean mass. [15][16][17][18][19] Although previous studies have recently shown the benefits of these linear measurements, particularly mid-thigh STT, 15,[17][18][19][20][21] the advantage of this formula has yet to be established in order it can be routinely used, i.e. in the labor ward, where it could be most useful.…”

Use of ultrasound fetal shoulder soft tissue thickness measurement in estimation of fetal weight

“…Another parameter, FSTT, was strongly correlated with fetal AC and BW according to Scioscia et al The new formula derived by adding FSTT showed higher efficacy than the Shepard and Hadlock formulas. 13 The utility of the new parameter was found by others to be valuable in macrosomia. 24 However, Chauhan et al did not confirm the correlation of FSTT as a predictor of high BW.…”

“…In our study, no significant correlation was found between HSTT and FW estimation and BW. Another parameter, FSTT, was strongly correlated with fetal AC and BW according to Scioscia et al The new formula derived by adding FSTT showed higher efficacy than the Shepard and Hadlock formulas 13 . The utility of the new parameter was found by others to be valuable in macrosomia 24 .…”

“…A few studies reported the feasibility and significance of the soft tissue thickness (STT) measurement incorporation approaches rather than biometric measurement alone for growth assessment and FW estimation prior to delivery 10,11 . In comparison to routine biometric parameter‐based formulas, the utilization of femur STT in BW estimation was found to be valuable 11–13 …”

“…10,11 In comparison to routine biometric parameter-based formulas, the utilization of femur STT in BW estimation was found to be valuable. [11][12][13] Although various formulas have been produced, an ideal formula that estimates FW with satisfactory accuracy has not been developed to date. 2,14 There are many factors that affect the accuracy of sonographic FW estimation: fetal and maternal reasons, complications of pregnancy, the gap between sonography and delivery, the experience of the person performing the sonography, and the quality of the sonography device.…”