The morphological aspects of the limbs as well as several details in the forearm and in the hand were observed from the seventh week of gestation on by routine sonographic examination of the embryo and the fetus. This examination was performed once a week beginning in the first months of life. The authors emphasize the value of sonography in the detection of fetal and embryonic malformations of the upper limb. The method has its limits however and remains to be perfected but it has already proved to be efficient for future studies, essentially because of its innocuousness. The images obtained between the 9th and 33d weeks of gestation are presented.