HDlive and 4D Ultrasound in the Assessment of Twin Pregnancy

Four-dimensional (4D) ultrasound facilitates the evaluation of fetal development, inter-human contact, and intra-pair stimu lation in twin pregnancies. HDlive is a new surfacerendering mode, which uses an adjustable light source that facilitates the ability to create lighting and shadowing effects, thereby increasing depth perception. In this article, we discuss recent topics regarding twin fetal development in the first and second trimesters of pregnancy, inter-twin contacts in the first trimester, the Kurjak antenatal neurodevelopmental test (KANET) in twin fetuses, and prediction of twin temperament using HDlive and 4D ultrasound. HDlive and 4D ultrasound may become an important modalities in future research on twin fetal neurobehavioral development, and assist in the evaluation of inter-twin relationships and differences in twin fetal temperament.