The nurses and doctor in the hospital refused to release me and my baby to go home if we insisted on not giving formula as supplement for the first week. But they do provide free formula in the hospital, so you don't need to bring your own. You might want to bring some bottles though coz the free nipples in hospital are fast flow.
The nurses and doctor said there were two reasons why they insisted me to suplement with formula before we left hospital:
1) neither my mother nor my husband's mother has ever breastfed babies, so no one would know how to help me at home. my sister has breastfed her baby, but she wasn't around at that time.
2) we hadn't found a pediatrician for our baby when we were in hospital, so they said if the baby couldn't get enough breast milk, no doctor could monitor his health condition.
But I found these are just common scenario for most new mothers though.
I think it is always a good idea to buy
some formula (say 5-6 cans) just in case you need them.I recommend ready-to-feed ENFAMIL A+.You can find it in the big
name stores like Walmart, Lablaws etc.
It is about $3 per can (235mL). If you do not need them,you can return back to as long as it is not pass the expire date.
Another good brand if similac which my first con use a few years ago.