Growth of the fetal lens and orbit

Objectives: To present normal lens and orbital measurement ranges by gestational age. Methods: Three hundred and thirty-five women with uneventful pregnancies were evaluated from the 15th to the 40th week of gestation. Lens and orbital measurements were added to routine biometric measurements for normal fetuses. Results: A strong linear correlation was observed between gestational age (GA) and lens diameter (R-2 = 0.89; P < 0.0001), circumference (R-2 = 0.89; P < 0.0001), and surface (R-2 = 0.90; P < 0.0001). A linear correlation was also found between GA and orbital diameter (R-2 = 0.92; P < 0.0001), circumference (R-2 = 0.92; P < 0.0001) and surface (R-2 = 0.95; P < 0.0001). A linear growth function was observed between biparietal diameter and both lens diameter (R-2 = 0.90; P < 0.0001) and orbital diameter (R-2 = 0.94; P < 0.0001). Conclusions: Lens and orbital measurements provide normative data for fetal growth and development. These data may be also helpful in detecting fetal ocular anomalies. (C) 2002 International Federation of Gynecology and Obstetrics. Published by Elsevier Science Ireland Ltd. All rights reserved.