Abstract
During the past decades, ultrasonic studies have revealed the fascinating diversity of fetal intrauterine activities. It has been shown that fetal activity occurs far earlier than a mother can register it, in fact as early as the late embryonic period. Analysis of the dynamics of fetal behavior has led to the conclusion that fetal behavioral patterns directly reflect developmental and maturational processes of fetal central nervous system. With 4D sonography it is possible to produce measurable parameters for the assessment of normal neurobehavioral development. There is urgent need for further multicentric studies until a sufficient degree of normative data is available and the predictive validity of specific aspects of fetal neurobehavior to child developmental outcome is better established.