A probe placement assistance method for fetal monitoring includes monitoring signal strength versus time (30) of a Doppler ultrasound signal (18) measured by a Doppler ultrasound probe (10). During the monitoring, human-perceptible guidance is presented to move the Doppler ultrasound probe along a trajectory. A peak in the signal strength versus time is detected which exceeds a threshold (T1, T2). Human-perceptible guidance is then presented to stop movement of the Doppler ultrasound probe. The signal strength versus time may be a signal strength value of the Doppler ultrasound signal for each time bin of a time sequence of time bins. The guidance may be repeated for different, e.g. orthogonal, trajectories until a peak exceeding a second threshold (T2) is reached, after which fetal monitoring begins.
