Heartbeat sound for baby sleep

What this sound is

The heartbeat in Agubu is, as the card in the app puts it, a resting pulse of 72 beats per minute, the pace you would feel with your head on someone's chest. A muffled, bass-heavy beat, then a short silence; there is almost no high-frequency content, so even a small speaker plays it softly without any edge. The tempo never changes; like a resting heart it is in no hurry. Unlike the womb sound there is no continuous hum on top: the pulse is bare. On its own it is the calmer sound; blended with a noise it moves closer to the womb environment.

Why it may help

The most consistent sound your baby heard before birth was your heartbeat: continuous, rhythmic and low. Many parents know a baby who calms on their chest; the heartbeat sound tries to call up that feeling without picking the baby up. The rhythm may help too: a slow, regular beat signals calm the way slow rocking does. On the evidence, we know of no recent study of heartbeat sounds in babies specifically, and evidence for steady sounds in general is weak and mixed. We cannot promise it works for every baby; try it low for a few nights and read Agubu's sleep log.

Safe use

Soft and bass-heavy, the heartbeat never sounds unpleasant even when loud; the volume rule still applies and is explained in the white noise guide.

• Keep the volume low: the level recommended for hospital nurseries is about 50 decibels. The practical test is simple: if you can talk in a normal voice in the room and still be heard easily, the level is fine; if the sound drowns you out, it is too loud.
• Do not put the phone or speaker in the cot or on its edge. Keep it at least one to two metres away, and avoid headphones, sound toys attached to the cot and any speaker close to the baby's ear.
• Use the timer. Fading the sound out 20 to 30 minutes after your baby has fallen asleep is usually enough. If you leave it on through the night, keep the level genuinely low.
• Turn it down once your baby has settled, and do not let a loud setting become the habit even briefly. Do not leave it running all day while your baby is awake, because it masks the speech they learn from.
• Play the heartbeat from across the room, not from a speaker near your baby's chest; however soft the sound, the distance rule does not change.

How to play it in Agubu

1. Open Agubu, go to the Sounds tab at the bottom and tap the Heartbeat card under Womb. This sound is in the free tier; there is no account to create and nothing to download, it plays on your device offline.
2. Set the volume with your own ears first: if you can speak in a normal voice in the room and still be heard, it is low enough. Place the phone one to two metres from the cot.
3. Tap Timer and pick a duration. When it runs out the sound does not stop abruptly; it fades down slowly. Twenty to thirty minutes after your baby has fallen asleep is enough on most nights.
4. If you like, layer it in the Mixer: combining the heartbeat with white noise or the womb sound is the most common blend. The Mixer is a Premium feature and blends up to four sounds at separate levels. Sounds play without ads and the app needs no internet connection.

When to use it

• In the newborn weeks at the settle to sleep, especially when moving your baby from your arms to the cot.
• In the evening fussy hour, after calming your baby on your chest, to keep the same feeling going.
• At night wakings when you want to settle your baby without picking them up, kept very low.