I think other wide neck bottles will fit in the Avent sterliliser but pretty sure you need the Avent ones for the breast pump.
I had 6 big bottles and 2 smaller ones when I had DS. I found that was enough as the sterliser only fits 6 in it. When he got bigger I still used the small ones for water in between feeds.
Good idea to be organised even though you plan to breastfeed. I didn't get anything when I had DS as stupidly thought b/f would be a breeze. Unfortunately, it didn't work out and I had to send DH round to my sisters at 11 at night to get the sterliser she bought us then go to a 24hr Tesco to get cartons of formula!!
There's so much to learn! I'm trying to keep an open mind as much as possible about everything. I know I want to breastfeed but my mum had problems and so I'm going to be prepared for every possibility. Also, I'm hoping it with get OH involved with the feeding too when I need a break.
I sounds like its going to be best to get everything in the same make and then I can't have any issues!!
I also plan to breastfeed but had one bottle last time and expressed when I had problems - we got the rest of the bottles later. I guess it would depend what your palns are - if you want to breastfeed you do need to go in prepared but also aiming for success so I probably wouldn't buy a huge amount of bottles (maybe 2-4 max) - you can always get the rest later. I used a liquid sterilant as it was cheaper than a steriliser, but if you already have a steriliser that will make your life easier. Start with just one tin of formula - it'll be easy to get more and newborns don't drink all that much (I'll regret saying that I know)
I had a breast pump that did not take the bottles I used - I used the bottle it came with and poured into the one I wanted her to drink from before streilising both (needless to say I didn't express all that much)
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