Research Article

Ultrasound Measurements of Fetal Thyroid: Reference Ranges from a Cohort of Low-Risk Pregnant Women

Table 3

Equations for fitting the 10th, 50th, and 90th centiles for each fetal thyroid lobe measurement according to gestational age.

Longitudinal diameter
P10: −1.2000 + 0.4429 (GA)P50: −0.3680 + 0.5120 (GA)P90: 0.6833 + 0.5833 (GA)

Anteroposterior diameter
P10: −0.2077 + 0.1615 (GA)P50: 0.0056 + 0.2056 (GA)P90: −0.0647 + 0.2647 (GA)

Transverse diameter
P10: 0.1789 + 0.1632 (GA)P50: 0.0136 + 0.2227 (GA)P90: 0.0647 + 0.2882 (GA)

Volume
P10: −155.95 + 11.38 (GA)P50: −282.31 + 20.68 (GA)P90: −457.81 + 35.98 (GA)