Sonographic measurement of ear length among normal fetuses of pregnant Igbo women in port Harcourt, Nigeria

Abstract

Background: Fetal ear length measurement has been associated with some clinical values: sonographic marker for chromo- somal aneuploidy and for biometric estimation of fetal gestational age.
 Objectives: To establish a baseline reference value for fetal ear length and to assess relationship between fetal ear length and gestational age.
 Methods: Ear length measurements were obtained prospectively from fetuses in 551 normal singleton pregnancies of 15 to 41 weeks gestation. Normal cases were defined as normal sonographic findings during examination plus normal infant post-delivery. The relationship between gestational age (GA) in weeks and fetal ear length (FEL) in millimeters were analyzed by simple linear regression. Correlation of FEL measurements with GA, biparietal diameter (BPD), Head circumference (HC), Abdominal Circumference (AC), Femur Length (FL) and maternal age (MA) were also obtained.
 Results: Linear relationships were found between FEL and GA (FEL=0.872GA-2.972). There was a high correlation between FEL and GA (r = 0.837; P = .001). Good linear relationship and strong positive correlation were demonstrated between FEL and BPD, AC, HC, and FL (p<0.05).
 Conclusion: The result of this study provides normal baseline reference value for FEL. The study also showed good linear relationship and good correlation between FEL and fetal biometric measurements.
 Keywords: Fetal ear length; sonographic measurement; chromosomal aneuploidy.

Measurement of the Fetal Ear Length Has No Clinical Value

“…The fetal ear length measured during ultrasound examination has already been the subject of some medical articles which focus on the creation of normal ranges of fetal ear length. When analyzing the normal ranges presented in the literature [6,12,13], it can be shown that the ranges are consistent with the normal ranges of the fetal ear length shown in this paper based on the data from our tertiary center. The available literature focuses mainly on the assessment of the fetal ear in terms of aneuploidy, such as trisomy 13, 18, and 21, and finds quite a statistically significant correlation between aneuploidy and smaller ears in fetuses observed in prenatal life [14][15][16][17][18].…”

“…Embryogenesis is the stage where the external ear is developed. The ear is visualized most often as a hyperechogenic structure in ultrasound examinations and is most often observed in the longitudinal plane [6]. The structure of the fetal ear which is observed during ultrasound examination is the ear auricle in the longitudinal plane.…”