When should I change from over-arm to under-arm swaddling?

New-born babies usually like to be swaddled over-arm. This gives them the secure feeling that they were used to in the womb, which can help them to settle to sleep better. You will probably find that anywhere between 3 and 6 weeks of age, your baby prefers to sleep with under arm swaddling, but still with the nice comfortable wrap around his tummy. However, all babies are different, and you will soon get to know what suits your own baby best.