Fetal pseudoascites: further anatomic observations.

A sonolucent band associated with the fetal abdominal wall is frequently observed in the normal obstetrical ultrasound examination. This band has been labeled pseudoascites because it may closely mimic intraperitoneal fluid. Fifty-three consecutive fetuses were examined sonographically; pseudoascites was evident in 45 fetuses. Sonographic anatomic observations identify pseudoascites as the fetal abdominal wall musculature. The anatomic description of pseudoascites, as well as the difference between pseudoascites and fetal intraperitoneal fluid, are discussed.