Yes, this is actually the best time to start. If your baby weighs between 2.2-3.8kg at birth please choose the SWADDLE UP™ in size Newborn.
If your baby weighs between 3.5-6kg at birth, please choose the SWADDLE UP™ in size Small.

While there is some crossover in size, we highly recommend you do not move into size Small unless or until your baby is at the upper limit of size Newborn. Using a SWADDLE UP™ or any garment that is too big for your baby can be dangerous for your baby as excess fabric can be a hazard.
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