Obstetrics · Growth

Fetal Growth Assessment

Enter ultrasound biometry to estimate fetal weight and see its centile for gestational age.

Ultrasound measurements

Head circumference, abdominal circumference and femur length, in millimetres.

Gestation — weeks

+ days

Head circumference (mm)

Abdominal circumference (mm)

Femur length (mm)

Please enter head circumference, abdominal circumference and femur length.

Centile

Z-score

3rd	10th	50th	90th	97th

Estimate only. Sonographic weight estimation carries a margin of error of around 10–15%. A single measurement is a snapshot — growth is best assessed as a trend over serial scans, and always alongside the full clinical picture. Please discuss this result with Dr McCaffrey.

Estimated fetal weight formula: Hadlock FP, Harrist RB, Martinez‑Poyer J. In utero analysis of fetal growth: a sonographic weight standard. Radiology 1991; 181: 129–133 (HC/AC/FL method). Centile reference: Stirnemann J et al. International estimated fetal weight standards of the INTERGROWTH‑21st Project. Ultrasound Obstet Gynecol 2017; 49: 478–486.