They do recommend washing anything that will come into contact with baby before use. So that's all clothes, sheets, towels, etc. New clothing etc can have chemicals left over from manufacture that can irritate baby's skin which is why they tell you to wash everything.
I didn't use a special powder, just my normal powder.
As for what to take to hosp, I have a combination of 4x0 and 3x0. My niece was 9lbs 6oz (2.45kg) at birth and fitted into both 4x0 and 3x0. She didn't last long in 4x0 but she did fit them for a few months after birth.
So I'd recommend taking both I guess! That's what I'm doing anyway.
Unless you have a premmie baby or a very small baby who might be too little for 4x0!
I had only washed 2 of my 0000 clothes and then just the 000, i am glad i did this as bub was 9lb 3oz and only fitted the 0000 clothes for 3 weeks. I took one 0000 and one 000 sized outfits to hospital as they supplied stuff while there.
I wash everything (for bub/kids/us) before we wear it, because as has been said before there can be chemical residue on them and I just dont want to risk it. Plus we have sensitive skin.
AS for washing powders, a lot of people with top loaders use Lux flakes (pure soap) for bubs clothes. Front loaders, Amolin or Purity are some of the low allergy ones.
We use Amolin for everything as we have a f/l at the moment, but Iam investigating using soap nuts..still researching.
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