ABSTRACT
Fetal motility is considered to reflect the developing nervous system but also involves functional and maturational properties of fetal hemodynamics and the muscular system. The introduction of four-dimensional (4D) sonography was a turning point in the assessment of fetal behavior by providing the capability of simultaneous spatial imaging of the entire fetus and its movements 1 – 9 (Figure 22.1). Indeed, sonographic studies have revealed the fascinating diversity of fetal intrauterine activities. It has been shown that fetal activity occurs far earlier than a mother can perceive – in fact as early as the late embryonic period. Furthermore, the qualitative and quantitative ranges of behavioral patterns expand rapidly as pregnancy progresses, and random movements of the fetal body, which are the earliest signs of fetal activity, change into well-organized behavioral patterns observed late in gestation. From the analysis of the dynamics of fetal behavior, it has been concluded that fetal behavioral patterns directly reflect the developmental and maturational processes of the fetal central nervous system.
