In Toronto, it depends on the hospital .. but maybe only 3 were supplied by them for my 1st.
Calculate a 2 day stay with changing them every 4 hrs .. that's how many.
We are in Alberta and I work on L&D we provide all pampers diapers no cost including wipes. We only packed a couple for our going home bag.
Some hospitals have some for you to use while there. Depending on how long you are staying then rule of thumb is change every 3-4 hours unless it's a poopy nappy.
Take a package of diapers