The world of a child in utero is far from silent. Between the 13th and 16th weeks of pregnancy, your fetus’ ears will begin to develop – and this is when your womb transforms into a state-of-the-art sound system where he can enjoy the comforting sounds of your heartbeat and voice. But your child does not just hear what is on the inside. He can also tune into the music you are listening to or the movie you are watching through the vibrations of your amniotic fluid. Simply put, you have an eavesdropper inside.