A morphometric analysis of the fetal craniofacies by ultrasound: fetal cephalometry.

We present here a set of 24 standardized linear measurements that describe the growth of different craniofacial structures in the normal fetus from 16 to 36 weeks of gestation. These measurements were taken from 89 pregnant women, who had from 1 to 3 ultrasonographic evaluations during the pregnancy (16, 26, and 36 weeks of gestation). All the values presented here were obtained using the technique described by Escobar et al. The mean and standard deviation was calculated for each measurement and was used to estimate the normal growth pattern of each variable. Approximate confidence intervals for the mean of each variable were constructed for use in identifying unusually low or high values. The confidence intervals are available in graphic form by request. These data will not only contribute to an understanding of fetal craniofacial growth and development in utero, but in addition, it will help to make the diagnoses of mild craniofacial anomalies that would not be detected by the routine ultrasonographic examination. We suggest that this procedure should be included if not in all routine obstetrical ultrasound evaluations, then at least in the more extensive level II obstetrical ultrasound.