When can fetal heart sounds typically be detected using a stethoscope?

Fetal heart sounds can typically be detected using a stethoscope around week 20 of pregnancy. This is when the uterus has grown sufficiently and the fetal heart has developed enough to be audible through the maternal abdomen without electronic equipment.

Around this time, the fetus is large enough, and the amniotic fluid provides adequate transmission of sound, allowing for the detection of the heartbeat by listening over the mother’s belly. While some practitioners might be able to hear fetal heart tones as early as 18 weeks, this is less common and not the standard timeline for using a stethoscope. Therefore, week 20 is recognized as the more typical point at which fetal heart sounds are reliably detected by this method.