How to Swaddle a Baby Safely and When to Stop Swaddling

Why swaddle at all

• A snug wrap can calm the startle reflex that jolts newborns awake and is one of the classic soothing tools for crying (see the colic guide).
• Swaddling is optional. Plenty of babies sleep well without it, and some clearly dislike it. Arms in, one arm out, or a plain sleep sack are all fine choices.

How to swaddle, step by step

1. Lay a thin, breathable blanket in a diamond and fold the top corner down about 6 inches (15 cm).
2. Place the baby on their back with the shoulders just below the fold.
3. Bring one side across the chest and tuck it under the body, arm straight but relaxed at the side.
4. Fold the bottom corner up loosely over the feet, leaving plenty of room.
5. Bring the other side across and tuck it behind the back.
6. Check the fit: you can slide two or three fingers between the blanket and the chest. Snug at the arms, loose at the hips.
7. Fastened or zip swaddle sacks do the same job and are harder to wriggle out of. Follow the size chart.

Hip-healthy swaddling

• Legs need to bend up and fall open at the hips, like a frog. Wrapping legs straight and tight can contribute to hip dysplasia.
• If your baby was breech, has a family history of hip problems, or had a hip check flagged, ask at the next visit which style suits them.

Safe-sleep rules that go with a swaddle

• Always on the back. A swaddled baby who ends up on their tummy is at higher risk.
• Nothing loose in the crib, and the swaddle itself must stay snug enough not to ride up over the face.
• Don't use weighted swaddles, weighted sleep sacks or weighted blankets. The AAP advises against them.
• Avoid overheating: a light layer under the swaddle is usually enough. Feel the chest or the back of the neck; sweating or flushed skin means too warm. See the room temperature guide.
• Give lots of unswaddled awake time for kicking and tummy time.

When to stop

• Stop swaddling for sleep as soon as the baby shows any sign of trying to roll. The AAP notes this often starts around 2 months, sometimes earlier, so watch from about 8 weeks.
• Transition options: one arm out for a few nights, then both arms out; or move straight to an unweighted sleep sack. Expect a few rougher nights, which usually pass within a week.

Common mistakes

• A swaddle so loose the blanket comes free in the crib.
• Wrapping the legs straight.
• Swaddling a baby who sleeps in the parent's bed, a swing or on a sofa.
• Continuing after the baby can roll.

When to check in

• Mention it at a checkup if your baby seems to hate every swaddle and every sleep sack and you want other soothing ideas.
• Ask about hips if one leg seems shorter, the thigh skin folds look uneven, or one hip doesn't open as easily as the other during diaper changes.