Hemivertebra is a rare congenital spinal anomaly where only one side of the vertebral body develops, resulting in deformation of the spine, such as scoliosis, lordosis, or kyphosis. We aimed to determine the incidence and clinical characteristics of hemivertebra. We present three fetuses with a prenatal ultrasonographic diagnosis of hemivertebra at 15-22 weeks' gestation, and we determine the incidence and clinical characteristics of hemivertebra among 78,500 live-born infants at a tertiary medical center in Israel. There were 26 cases of hemivertebra (0.33/1,000 live-born infants): male/female ratio 1/1, Jewish/Arab ratio 10/16, and ratio of single/multiple type of hemivertebrae 17/9. Twenty-three out of 26 infants (88.5%) with hemivertebra had additional congenital anomalies (cranial, cardiac, renal, intestinal, and skeletal). Hemivertebra is not an infrequent finding in fetuses and live-born infants. Comprehensive ultrasonographic screening of the fetus allows early prenatal diagnosis of hemivertebra, and provides parents with helpful information for their decision regarding the fate of pregnancy. Copyright (c) 2005 S. Karger AG, Basel.