10 Reasons a Baby Heartbeat Recording May Sound Unclear

1–3. The room, notifications and fabric

An open window, fan, TV or conversation can easily overwhelm a quiet sound. A call or vibration interrupts the session. Clothing, blankets and bedding can also create loud rustling close to the microphone.

4–5. Phone movement and breathing

Even slight movement of the phone can create a low rumble. Deep or held breaths also change the recording. Get comfortable first and breathe naturally.

6–7. The case and microphone condition

A case may cover an opening or rub against the phone. Dust, damage and model-specific design can affect sensitivity. Make a short voice recording and check your phone’s instructions.

8. Gestational age

In earlier weeks, an ordinary microphone has more difficulty capturing quiet internal sounds. Bubbi suggests 18–22 weeks as a practical guide but cannot guarantee a result on any particular day.

9. The baby’s and placenta’s position

Your baby moves, while the placenta and other tissues sit between the source of a sound and the phone. A spot that worked yesterday may not produce the same result today.

10. Sounds from the mother’s body

Pulse, blood flow, digestion and breathing create rhythms of their own. They may mask or imitate other sounds. Do not try to identify the source yourself.

When to stop

Take a break after one short attempt. An unclear file is a technical result, not a medical sign. Contact a healthcare professional if you are concerned about symptoms or your baby’s movements.