Craniofacial inclination at 14 to 39 weeks' gestation in normal Korean fetuses

Objectives - The purpose of this study was to evaluate a normal range for prenatal craniofacial inclination using images of fetal profiles at 14 to 39 weeks' gestation in normal Korean fetuses. Methods - We conducted a cross-sectional study of 308 normal fetuses at 14 to 39 weeks' gestation. After the exclusion of images with inadequate quality, the sagittal plane of the sonographic fetal facial profile from 250 normal fetuses was evaluated. The frontomaxillary facial, frontonasal, maxilla-nasion-mandibular, and mandibulomaxillary facial angles were measured and are presented according to gestational age. Results - The overall mean frontomaxillary facial angle ± SD was 86.0° ± 7.6° between 14 weeks 6 days' and 39 weeks 2 days' gestation without a significant association between the frontomaxillary facial angle and gestational week. The overall mean frontonasal, maxilla-nasion-mandibular, and mandibulomaxillary facial angles were 125.8° ± 7.2°, 4.7° ± 3.3°, and 83.2° ± 8.5° between 14 weeks and 39 weeks 6 days. There was a significant linear correlation between gestational age and the frontonasal angle (r = - 0.1534; P = .0187; y = -0.188 × gestational age + 130.7), maxilla-nasion-mandibular angle (r = -0.2773; P < .0001; y = -0.160 × gestational age + 9.0), and mandibulomaxillary facial angle (r = -0.2861; P < .0001; y = -0.432 × gestational age + 94.6). Conclusions - We provide preliminary normative data for fetal facial angles related to craniofacial inclination across gestational ages in normal Korean fetuses. These data may be of help not only for the understanding of normal facial growth in utero but also for diagnosis of abnormal fetal facial dimensions.