Sonographic evaluation of fetal adrenal glands.

Seventy-five consecutive pregnant patients at 15--40 weeks of gestation underwent sonography, with special attention to identification of the fetal adrenal gland. The gland was found in 12% of fetuses of less than 26 weeks gestation and 90% of fetuses of more than 26 weeks. The gland characteristically has two long limbs that are relatively anechoic (thought to be the fetal zone of the cortex) and a central echogenic line in each limb (presumed medulla). The changes seen in the adrenal gland as pregnancy progresses are reviewed and correlated with the adrenal glands in newborn infants.