Provided is an ultrasound diagnosis apparatus including: a probe configured to receive echo signals from a fetus； a processor configured to acquire Doppler data based on the received echo signals, determine a heart rate of the fetus based on period information of the Doppler data, and modulate, based on the determined heart rate, a heartbeat Doppler sound of the fetus, which is acquired from the Doppler data, into a heartbeat sound that is similar to a sound of an actual heartbeat； and a speaker configured to output the heartbeat sound.
