Fetal maxillary and mandibular length in normal pregnancies from 11 weeks' to 13+6 weeks' gestation: A Taiwanese study

ObjectivesThis study aims to establish the normal range of maxillary and mandibular lengths within the Taiwanese population at 11+0 weeks to 13+6 weeks of gestation in normal singleton pregnancy as a reference value for prenatal ultrasonographic examinations.Materials and methodsWe examined nuchal translucency in 269 normal singleton pregnancies, with the gestational age ranging from 11 weeks to 13+6 weeks in this study. Fetal biometric measurements, with an emphasis on maxillary and mandibular lengths, were obtained from the patients during consecutive routine prenatal ultrasonographic examinations.ResultsMaxillary and mandibular lengths were recorded successfully in 191 patients and 179 patients, respectively. The mean maternal age was 31 years (range 19–45 years), with a corresponding gestational age of 12 + 4 weeks (range, 11+0–13+6 weeks). A first-degree correlation was found to exist between the gestational age and maxillary length (r = 0.596; p < 0.0001; y = 1.491 × GA − 10.523) as well as mandibular length (r = 0.465; p < 0.0001; y = 1.050 × GA − 6.50).ConclusionNormative data for ultrasonographic measurements of maxillary and mandibular lengths within the Taiwanese population were presented. Our data can serve as a reference value in congenital anomaly screening during prenatal examination.