Using a Doppler ultrasound device, fetal heartbeats can be detected by the twelfth week of pregnancy. Options: Using a Doppler ultrasound device, fetal heartbeats can be detected by the twelfth week of pregnancy.Fetal heartbeats can be detected by the twelfth week of pregnancy, using a Doppler ultrasound device. Detecting fetal heartbeats by the twelfth week of pregnancy, a physician can use a Doppler ultrasound device. By the twelfth week of pregnancy, fetal heartbeats can be detected using a Doppler ultrasound device by a physician. Using a Doppler ultrasound device, a physician can detect fetal heartbeats by the twelfth week of pregnancy. Correct: E