how far along do you have to be to hear baby's heartbeat?
Full Answer. If an early ultrasound is not done, the first chance to hear a baby's heartbeat is at about 10 weeks of gestation using a fetal Doppler, which is a handheld ultrasound device. Baby Center points out, however, that it is more common to pick up a heartbeat with a fetal Doppler device at 12 weeks.