Womba is a patented musical instrument designed for an unborn child in the womb. In seeking to leverage the abundant research showing that fetuses can respond to, benefit from, and interact with external stimuli, we built the Womba as an instrument to explore prenatal musical potential and new possibilities for artistic expression. The Womba is a comfortable belt worn around an expecting mother’s belly. The baby’s in utero movements are detected with embedded sensors and mapped to sound played via speakers to the baby, as well as the outside world. The location and strength of the baby’s movements are also visualized with light patterns on the belt. The mother can choose the sound palette and mapping strategies, as these are typically personal aesthetic decisions that could be influential to the child’s personality development. The Womba could also be played externally, opening up the possibility of the mother or father playing a duet with the baby as well. The Womba proposes to be a creative tool for nurturing a child’s physical and psychological development, promoting parental bonding, and offering new possibilities in fetal research and artistic exploration.