Yes, I put the block in as soon as their eyes open. I use Mazuri. I don't feel they are too big that they could choke the baby. Actually, I feel the opposite ... they are big enough that babies are not able to swallow them to get them lodged in their throat or choke on them. I have never had a baby choke on them.
I think the smaller the pieces the easier it would be to swallow and choke on. JMHO ! However, like Anne I use them for teething and for them to nibble on. They also try to play with them. It is really cute to watch.
If you feel the pieces are too big they are easily broken into pieces. Problem solved.
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